Auto Warz — Research Tree Design¶

Document Type: Design Document Version: 0.8 Last Updated: 2026-09-05 Vault destination: 01_Design Documents Phase: Phase 1 — Launch release (Industrial branch). Exploration branch in the Space Update, Military branch in the Phase 2 War Update Related Documents: [01_Master GDD](<../01_Master GDD.md>) · [04_Factory & Resource System Design](<../Systems/04_Factory & Resource System Design.md>) · [06_Vertical Layers & Core Power System](<../Systems/06_Vertical Layers & Core Power System.md>) · [07_Pipe & Fluid System Design](<../Systems/07_Pipe & Fluid System Design.md>) · [35_Economy Design](<../Systems/35_Economy Design.md>) · [00_Canonical Design Facts](<../../04_Project Management/00_Canonical Design Facts.md>) Folder: 01_Design Documents

0. Reconciliation Status (RESOLVED)¶

This document is the single authority for the research tree. It is amended in place, branch by branch, not rebuilt.

0.1 Why amend rather than rebuild¶

The tree was written 2026-02-27 and never revisited while every system around it changed, which made "is any of this still true" a fair question. The answer is that the model is current and only the branch contents are stale:

Still correct	Evidence
Branching prerequisite graph, no tier gates	Matches research is path-choice, not a timeline (`[25_Power System Design](<../Systems/25_Power System Design.md>)` §2.1)
~~Session-scoped, resets each session~~	⚠️ Corrected 2026-09-05 — see §0.4. The model is right; the word was wrong. Research is world-scoped.
RP from Science Drives plus Field Data	Unchanged
Concurrent slots, shared pool in multiplayer	Unchanged
Pausing with no cancellation	Unchanged
Infinite nodes and the Full Tree Bonus	Unchanged

None of that conflicts with anything decided since. Rebuilding would rewrite all of it in order to fix a problem that lives entirely in the branch listings, which is discarding working design to solve a different one.

What is stale is bounded and tracked: Branch 2 has no transmission nodes and is missing three generators (OI-244, OI-245); there is no environmental branch (OI-248); and branches 1, 3, 4, 5, 6 and 7 have not been audited since (OI-246).

0.2 The structural fix that had to come first¶

You cannot amend "the tree" while two documents describe different ones.

[04_Factory & Resource System Design](<../Systems/04_Factory & Resource System Design.md>) carried its own Industrial Research Branch listing, and it did not merely use different node names. It was organised into TIER 1 to TIER 4 gates, which this document explicitly forbids — "There are no tier gates; progress is determined entirely by what you've already researched." Two documents describing the same system on opposite structural models is not drift, it is a fork.

It had also gone stale in its own right: it unlocked Smart Buffers, a building deleted under OI-020; Assembly Machine Mk2, though Mk levels are not researched at all (Canonical §4); and a roof-mounted power pole module, since redefined as a transmitter range extender.

That listing is deleted, and 04_Factory now points here. This document owns the tree; other documents name nodes but never restate the structure.

⚠️ Deleting it exposed a gap it had been hiding. That listing was the only place Power Management and Bot Programming I/II were ever written down, and four references across 04_Factory and 01_Master GDD gate real features on them — the Power Priority System, the Construction Bot Bay and Genesis automation. Because the listing contradicted this tree's structure, those nodes were never actually in the tree; the fork merely made it look as though they were. Tracked as OI-322.

0.3 How amendments are made¶

Branch by branch, each as its own tracked item, each stating what it changes and why. A branch that has been checked against current design says so and carries the date, so the next reader can tell audited and correct from not yet looked at — which is the distinction this document lacked for six months.

0.4 Amendment, 2026-09-05 — world-scoped, and the second tree¶

Two changes, both structural, neither touching a branch listing.

The word "session" was doing two jobs¶

This document said research was session-scoped and reset at the start of every new session. Read with the vocabulary now locked in [04_Data Dictionary](<../../05_Reference/04_Data Dictionary.md>) §0, that says a player loses their entire tech tree when they go to bed, which was never the intent.

Research is world-scoped. It resets in a new world. It survives a logout.

A world is the persistent universe and the save file. A session is one sitting, and no game state belongs to one. Nothing about the design changes; every mechanic below is unaffected. Only the word was wrong, and it was wrong in a way that would eventually have been implemented literally.

There is a second tree, and this document does not own it¶

Engineering Research is account-scoped and improves ship and mothership designs. It is defined in [35_Economy Design](<../Systems/35_Economy Design.md>). This document owns Factory Research and only that.

	Factory Research (this document)	Engineering Research (`[35_Economy Design](<../Systems/35_Economy Design.md>)`)
Scope	World	Account
Structure	Branching prerequisite graph, no tier gates	Flat catalogue of upgrade lines
Unlocks	Capability: buildings, recipes, logistics tiers, vertical levels	Nothing. Raises rates only.
Paid with	Research Points, from Science Drives and Field Data	Engineering Points, from player levels
Resets	New world	Never

The split is by what resets and what accumulates: the factory is rebuilt in every world, so its tech resets; the mothership travels between worlds, so its tech travels.

Engineering Research is flat rather than branching on purpose. Prerequisites exist to sequence content, and it has no content to sequence. Flat also enforces its guard rail by construction: account research improves capacity and efficiency, it never unlocks capability. There is nothing to unlock, only things to raise, so nobody can add a node granting a weapon a new player cannot build.

⚠️ The Infinite Level nodes stay here¶

An earlier note in the war layer design suggested the infinite nodes would move to Engineering Research. They do not, and moving them would be a mistake.

Every one of them raises a factory rate — RP rate, turret damage, Genesis speed, module effects, extraction rate — and every one is world-scoped. Moving them to an account-scoped tree would turn a long grind into permanent cross-world power, which is exactly what [00_Canonical Design Facts](<../../04_Project Management/00_Canonical Design Facts.md>) §20 forbids.

Engineering Research has its own uncapped lines. They are a different thing that happens to share a shape.

Research Points are unchanged¶

Stated because it was an open question. RP comes from Science Drives and Passive Field Data, and contribution does not feed it. Linking war contribution to RP would make the war a shortcut past the factory rather than a consumer of it. See [35_Economy Design](<../Systems/35_Economy Design.md>).

0.5 Amendment, 2026-09-06 — Branch 6, buildings stop being unlocks¶

OI-361. One change, structural, touching two nodes and the branch's audit note.

All buildings tier, so no building is a research unlock¶

El decided 2026-09-06 that every building tiers. Under [00_Canonical Design Facts](<../../04_Project Management/00_Canonical Design Facts.md>) §4 that means by upgrade kit — four universal items, applied in place by Genesis, preserving modules, port configuration and contents — and explicitly not by research: "Research unlocks recipes; a recipe may require a Mk-N building."

The 2026-08-30 audit defended Reinforced Wall and Heavy Turret as "distinct buildings rather than Mk levels, so they are legitimate research unlocks." That reasoning is now withdrawn. They are Mk levels.

What those two nodes unlock instead¶

Node	Was	Now
Advanced Fortification	Reinforced Wall + gate automation	Gate automation only. A wall reaches higher HP by kit
Turret Upgrade II	Heavy Turret (2×2, higher damage, ammo: Hull Plating)	Hull Plating ammunition, requiring a Turret at Machine Mk2 to chamber

Turret Upgrade I is a flat effect on the building and is unaffected. The Combat Doctrine infinite node is unaffected.

⚠️ What a higher rung of ammunition does, and does not do¶

Decided 2026-09-06 (OI-362). Better ammunition raises rate of fire, range and spread.

Ammunition does not hit harder. It hits more often, further out, and wider.

Damage per shot is constant across the whole ladder, which has three consequences the branch's cost curve should respect:

Nothing goes obsolete. A Mk1 turret firing Metal Plates is never useless, only slow and short-ranged.
Every rung raises consumption. Rate of fire is the first term, so researching a better round is a commitment to enlarging the line that feeds it. Research is not free, and a player who unlocks a rung without scaling production ends up worse off than before.
Range and spread are geometry, so a new rung changes where turrets need to be, not only how many. That is a layout consequence, which is the kind this game is made of.

Full treatment in [38_Weapons & Ammunition Design](<../Systems/38_Weapons & Ammunition Design.md>).

0.6 Amendment, 2026-09-07 — Branch 7, research stops selling speed¶

OI-369. El decided 2026-09-07 that Genesis upgrades, and that research points at it. Working out how separated three mechanisms that the branch had collapsed into one.

Research unlocks capability. Kits and modules buy capacity. Canonical §4's rule, and the same reconciliation Branch 6 got on 2026-09-06.

Mechanism	Buys
Factory Research	Verbs. Things Genesis can do at all
Upgrade kits	Mk level. Speed, and queue depth
Modules	Capacity, tuned per Genesis

Deleted from Branch 7, because they sell capacity rather than capability:

Node	Replaced by
Genesis Build Speed I / II	Machine Mk
Genesis Mining Upgrade (the +30% part)	Machine Mk
Genesis Bulk Mining	A Productivity module
Genesis Task Queue Expansion	Mk buys queue depth

Genesis Mining Upgrade is not gone entirely: its unlock half survives as Genesis Multi-Resource Task, since mining several resource types in one task is a verb.

Kept unchanged: Genesis Repair and Auto-Repair, Genesis Demolish, Bot Programming I and II, Genesis Blueprint Execution, Genesis Level Transition, Genesis Task Priority, and the Genesis Optimisation infinite node — which stays here and stays world-scoped, since it is a factory rate, exactly as §0.4 established for all five infinite nodes.

RP totals move. The Genesis Abilities branch loses roughly 475 RP of finite nodes. The figure in the RP Cost Reference needs recomputing, tracked with OI-369.

Full treatment in [40_Genesis Design](<../Systems/40_Genesis Design.md>).

Overview¶

The Research Tree is a branching prerequisite graph — nodes unlock specific children, and some nodes require multiple parents before they become available. There are no tier gates; progress is determined entirely by what you've already researched.

The tree is divided into 8 tabbed branches. Each branch has its own RP cost curve — some branches are cheap and fast, others are expensive long-term investments. Players choose their own path through the tree based on how they want to play.

Research is world-scoped — the tree resets at the start of every new world, and survives a logout. There is no cross-world persistence. (Corrected 2026-09-05; see §0.4.)

Each branch also contains one Infinite Level node — a node with no upper bound that can be researched repeatedly for compounding multiplier bonuses. These are the long-term grind layer of the research system, rewarding a long-running world.

Completing every finite node in every branch unlocks a Full Tree Bonus — a permanent world-wide flat boost to supply chain contribution on top of the standard multipliers.

Research Points (RP)¶

Sources¶

Source	Rate	Notes
Science Drives (active)	High — consumed by Research Lab	Requires production chain investment
Passive Field Data	Low — trickles in from all running buildings	Always active — base rate per running building + bonus tied to actual throughput

Field Data Detail¶

Field Data has two components that stack:

Base rate: 1 RP per 10 ticks per running building — awarded just for existing and being powered. A stalled building waiting for inputs still earns base rate as long as it's powered.

Throughput bonus: Additional RP proportional to actual output rate. A Smelter producing 100 plates/min generates significantly more Field Data than one producing 10 plates/min. This rewards factory optimisation — a dense, efficient factory earns Field Data much faster than a sparse idle one.

field_data_rp = (running_buildings × base_rate)
              + sum(building_output_rate × throughput_multiplier)

Concurrent Research Slots¶

Slots	Unlock Condition
1 slot	Available from the start
2 slots	`Research Expansion I` node in Research & Science branch
3 slots	`Research Expansion II` node in Research & Science branch

In multiplayer: Research slots are a shared pool — one queue, any player can assign research to any available slot. Research Expansion unlocks apply to the world, not to individual players. The host's Research Lab output feeds the shared RP pool.

Pausing Research¶

Active research can be paused at any time — the invested RP is preserved. A paused node holds its progress indefinitely. The player can start a different node in that slot, then resume the paused node later when the slot is free. There is no cancellation — once RP is invested it is never lost, only held.

Branch Overview¶

#	Branch	Focus	Cost Curve	Tab Colour
1	Industrial	Factory buildings, recipes, belt upgrades	Medium, steady	Orange-Red
2	Power	Generators, core power, geothermal	Medium, front-loaded	Yellow
3	Research & Science	Labs, RP rate, concurrent slots	Low early, high late	Teal
4	Vertical Expansion	Underground levels, sky levels, vertical structures	High, gated	Blue
5	Exploration	Scanners, space travel, planet landing	High, Phase 2 focus	Purple
6	Defence	Turrets, walls, alien countermeasures	Medium	Olive
7	Genesis Abilities	New tasks, speed, range, automation	Low early, medium late	White
8	Modules	Module types and capability. Slots are not researched.	Medium, branching	Gold
9	Environmental	Waste treatment, remediation, farming	Optional, mid	Green

Branch 1 — Industrial¶

Audited 2026-08-30. Correct against current design. No Mk-gated nodes, no deleted buildings, and no splitter nodes for the Router to have orphaned. The Router needs no node and deliberately has none: splitting is fundamental enough that gating it would block the tutorial, so like the Basic Belt it is available from the start, and its Mk2 priority and Mk3 filtering come from Base Mk rather than research (Canonical §7a).

Unlocks the full factory building set, production recipes, and logistics upgrades.

Cost curve: 50 → 100 → 200 → 400 → 800 RP per node (doubles each depth)

[START]
    │
    ├── Basic Refining (50 RP)
    │       Unlocks: Refinery building, ref_metal_plate recipe
    │       ├── Advanced Refining (100 RP)
    │       │       Unlocks: ref_silicon_wafer, ref_copper_wire recipes
    │       │       └── Chemical Processing (200 RP)
    │       │               Unlocks: Chemical Plant building
    │       │               Unlocks: ref_fuel_cell, ref_polymer recipes
    │       │               └── Advanced Chemistry (400 RP)
    │       │                       Unlocks: fld_chemical_solvent production
    │       │                       Unlocks: Advanced Press building
    │       └── Component Assembly (100 RP)
    │               Unlocks: Assembly Machine building
    │               Unlocks: cmp_circuit_board, cmp_drive_core recipes
    │               ├── Hull Manufacturing (200 RP)
    │               │       Unlocks: Press Machine building
    │               │       Unlocks: cmp_hull_plating, cmp_structural_frame recipes
    │               └── Advanced Assembly (200 RP) [requires: Chemical Processing]
    │                       Unlocks: Advanced Assembly building
    │                       Unlocks: adv_quantum_processor recipe
    │
    ├── Belt Upgrade I (50 RP)
    │       Unlocks: Fast Belt (2× speed)
    │       └── Belt Upgrade II (150 RP)
    │               Unlocks: Express Belt (4× speed)
    │               └── Underground Belt (300 RP)
    │                       Unlocks: Underground Belt building
    │
    ├── Wire Extraction (50 RP)
    │       Unlocks: Wire Extruder building
    │
    └── Fluid Extraction (50 RP)
            Unlocks: Gas Pump building, Water Extractor building
            Unlocks: fld_coolant, fld_fuel production
            └── Liquid Metal Processing (200 RP) [requires: Advanced Refining]
                    Unlocks: fld_liquid_metal production
                    Unlocks: Insulated Pipe

⚡ INFINITE NODE — Deep Extraction
    Prerequisite: Belt Upgrade II + Fluid Extraction
    Effect: +2% extraction rate per level on all mining/harvesting/pumping buildings
    See: Infinite Level Nodes section

Branch 2 — Power¶

Audited and rebuilt 2026-08-30 against [25_Power System Design](<../Systems/25_Power System Design.md>) and Canonical §8 (OI-025, OI-244, OI-245).

Unlocks generation, transmission, distribution control and core power access.

Cost curve: 50 → 100 → 200 → 400 RP per node, doubling with depth. Deep Core Tap continues past that because it is the branch's long tail.

[START]
    │
    ├── Combustion Power (50 RP)
    │       Unlocks: Biomass Burner building
    │       └── Coal Firing (100 RP)
    │               Unlocks: Coal Generator building
    │               └── Fuel Power (200 RP) [requires: Fluid Extraction — Branch 1]
    │                       Unlocks: Fuel Generator building
    │
    ├── Solar Collection (75 RP)
    │       Unlocks: Solar Panel building (surface + sky levels)
    │       └── Energy Storage (150 RP)
    │               Unlocks: Accumulator building
    │
    ├── Wind Power (100 RP) [requires: Basic Construction — Branch 4]
    │       Unlocks: Wind Turbine building
    │
    ├── Power Distribution (75 RP)
    │       Unlocks: Power Pole building
    │       ├── Power Management (150 RP)
    │       │       Unlocks: per-building power priority, 1–5 scale
    │       │       Unlocks: brownout shedding order becomes player-controlled
    │       │
    │       ├── Power Grid Expansion (300 RP)
    │       │       Unlocks: Power Conduit (cross-level power)
    │       │       Unlocks: Power Pylon (sky level power)
    │       │
    │       └── Medium Voltage Transmission (300 RP)
    │               Unlocks: MV Transformer (step-up and step-down are one building)
    │               Unlocks: Transmission Line and its Pylons
    │               └── High Voltage Transmission (600 RP)
    │                       Unlocks: HV Transformer
    │                       Effect: 0.15% loss per tile against MV's 0.5%
    │
    ├── Core Power (150 RP) [requires: Combustion Power]
    │       Unlocks: Core Power Station building
    │       └── Deep Core Tap I (300 RP)
    │               Unlocks: Underground Level 2 core energy access (+35% CER)
    │               └── Deep Core Tap II (600 RP)
    │                       Unlocks: Underground Level 3 core energy access (+55% CER)
    │                       └── Deep Core Tap III (1200 RP)
    │                               Unlocks: Underground Level 4 core energy access (+80% CER)
    │
    ├── Geothermal Basics (75 RP)
    │       Unlocks: Geothermal Tap building
    │       └── Deep Geothermal (200 RP) [requires: Core Power]
    │               Unlocks: Geothermal Tap underground placement bonus active
    │
    └── Nuclear Fission (800 RP) [requires: Fuel Power + Waste Handling — Branch 9]
            Unlocks: Nuclear Reactor building
            See the cross-branch note in Branch 9 — a reactor cannot be
            unlocked before the means to handle its waste.

What changed in the rebuild, and why¶

Three nodes were deleted because they unlocked something that cannot be researched. Industrial Power → Fuel Generator Mk2, Advanced Solar → Solar Panel Mk2 and Industrial Geothermal → Geothermal Tap Mk2 all gated Mk levels, and Canonical §4 is explicit: "Mk is researched? No. Research unlocks recipes; a recipe may require a Mk-N building." Mk comes from upgrade kits, not RP. The nodes were not stale wording, they were unbuildable.

What replaced them is better than a like-for-like swap:

Deleted	Replaced by	Why this is an improvement
Fuel Generator Mk2	Combustion Power → Coal Firing → Fuel Power	A real generator ladder — biomass to coal to fuel — where each step buys more power for a different logistics cost (`25_Power` §5.1). The old node bought a bigger number
Solar Panel Mk2	Energy Storage → Accumulator	Solar dies every night and needs a bank to be viable at all (`25_Power` §5.1b). Storage is the actual solar upgrade, and it was previously unlocked by nothing
Geothermal Tap Mk2	(nothing)	Geothermal taps share one finite Geothermal Energy Pool, so a bigger tap does not mean more power — the pool is the limit. There was nothing for this node to sell

Transmission was the whole branch's missing half (OI-244). Canonical §8 has three tiers, Generation → Transmission → Distribution, and transmission is the entire research payoff of the power design — the answer to "my ore field is too far to reach". The branch previously had no transformers, no lines and no voltage tiers. Transmission extends Branch 2 rather than taking a branch of its own (OI-087): it is one tier of one system, and a separate branch would frame it as an alternative to power rather than part of it.

Power Management was referenced by 04_Factory and defined nowhere (OI-322). It sits under Power Distribution, because priority is a distribution-tier concern.

Nuclear takes a cross-branch prerequisite on Branch 9. See Branch 9.

Branch 3 — Research & Science¶

Audited 2026-08-30. Correct against current design. Every node unlocks a recipe, a building or a rate effect, which is the model the tree is meant to use.

Unlocks better research infrastructure, passive RP generation, and concurrent research slots.

Cost curve: 40 → 80 → 200 → 500 RP per node (low early, steep late)

[START]
    │
    ├── Science Drive Production (40 RP)
    │       Unlocks: sci_basic_drive recipe
    │       Unlocks: Research Lab building
    │       └── Advanced Science Drives (120 RP)
    │               Unlocks: sci_advanced_drive recipe
    │               Unlocks: Advanced Lab building
    │               └── Quantum Science Drives (400 RP) [requires: adv_quantum_processor]
    │                       Unlocks: sci_quantum_drive recipe
    │
    ├── Field Data Collection I (40 RP)
    │       Effect: Passive RP rate +25%
    │       └── Field Data Collection II (100 RP)
    │               Effect: Passive RP rate +50% (cumulative)
    │               └── Field Data Collection III (250 RP)
    │                       Effect: Passive RP rate +100% (cumulative)
    │
    ├── Research Expansion I (150 RP) [requires: Science Drive Production]
    │       Unlocks: 2nd concurrent research slot
    │       └── Research Expansion II (500 RP) [requires: Advanced Science Drives]
    │               Unlocks: 3rd concurrent research slot
    │
    └── Research Specialisation (200 RP) [requires: Advanced Lab]
            Effect: RP generation rate +20% for the branch currently being researched

⚡ INFINITE NODE — Research Acceleration
    Prerequisite: Research Expansion II
    Effect: +2% passive RP generation rate per level
    See: Infinite Level Nodes section

Branch 4 — Vertical Expansion¶

Audited 2026-08-30. Correct following the OI-013 pass, which replaced the generic Shaft with the three named vertical structures. The Power Conduit already had its own node, so nothing was orphaned.

Unlocks underground levels, sky levels, vertical structures, and cross-level transport.

Cost curve: 100 → 250 → 500 → 1000 RP (high cost — major capability unlocks)

[START]
    │
    ├── Basic Excavation (100 RP)
    │       Unlocks: Underground Level 1 grid
    │       Unlocks: Core Drill building
    │       Unlocks: Deep Scanner building
    │       └── Deep Excavation (250 RP)
    │               Unlocks: Underground Level 2 grid
    │               Unlocks: Geothermal Tap underground placement
    │               └── Advanced Boring (500 RP)
    │                       Unlocks: Underground Level 3 grid (where available)
    │                       └── Core Excavation (1000 RP)
    │                               Unlocks: Underground Level 4 grid (where available)
    │
    ├── Vertical Lift (150 RP) [requires: Basic Excavation]
    │       Unlocks: Item Lift structure (cross-level item transport)
    │       └── Sky Lift (300 RP) [requires: Basic Construction]
    │               Unlocks: Vertical Belt between sky levels and surface
    │
    ├── Pipe Pump (100 RP) [requires: Basic Excavation]
    │       Unlocks: Fluid Riser structure (cross-level fluids, upward flow)
    │       └── Sky Pipeline (200 RP) [requires: Basic Construction]
    │               Unlocks: Vertical pipes between sky levels
    │
    ├── Basic Construction (100 RP)
    │       Unlocks: Sky Level 1 grid
    │       Unlocks: Sky Platform building
    │       └── Elevated Construction (250 RP)
    │               Unlocks: Sky Level 2 grid
    │               Unlocks: Wind Turbine building
    │               Unlocks: Sky Radar building
    │               └── High Altitude Construction (500 RP)
    │                       Unlocks: Sky Level 3 grid
    │                       Unlocks: Atmospheric Harvester building
    │                       └── Advanced Atmospheric Construction (1000 RP)
    │                               Unlocks: Sky Levels 4–6 (where available per planet)
    │
    └── Power Conduit (150 RP) [requires: Basic Excavation, Power Grid Expansion]
            Unlocks: Power distribution between all vertical levels

Branch 5 — Exploration¶

Audited 2026-08-30. Correct against current design. Mostly Phase 2 content and largely untouched by the Phase 1 design work, which is why it drifted least.

Unlocks the scanner system, space travel prerequisites, and planet landing capabilities. Primarily Phase 2 content — early nodes available in Phase 1.

Cost curve: 100 → 300 → 600 → 1200 RP (high cost — Phase 2 gates)

[START]
    │
    ├── Basic Scanner (100 RP)
    │       Unlocks: Basic Scanner building (5 unit reveal radius)
    │       └── Advanced Scanner (300 RP)
    │               Unlocks: Advanced Scanner building (15 unit radius)
    │               Unlocks: Planet count shown per revealed system
    │               └── Deep Space Array (600 RP)
    │                       Unlocks: Deep Space Array building (40 unit radius)
    │                       Unlocks: Biome types shown per revealed planet
    │
    ├── Shipyard Basics (300 RP) [requires: Advanced Scanner] ← Phase 2
    │       Unlocks: Shipyard building
    │       Unlocks: basic ship hull recipe
    │
    ├── Heat Shielding (300 RP)
    │       Unlocks: Landing on Lava Planets
    │
    ├── Atmospheric Filter (300 RP)
    │       Unlocks: Landing on Carbon Planets
    │
    ├── Sealed Habitat (400 RP) [requires: Atmospheric Filter]
    │       Unlocks: Landing on Rogue Planets
    │
    ├── Pressure Hull (400 RP) [requires: Heat Shielding]
    │       Unlocks: Landing on Mini-Neptune cores
    │
    ├── Thermal Isolation (600 RP) [requires: Pressure Hull, Heat Shielding]
    │       Unlocks: Landing on Hot Jupiters
    │
    ├── Heavy Shielding (800 RP) [requires: Thermal Isolation, Sealed Habitat]
    │       Unlocks: Landing on Chthonian Planets
    │
    └── Orbital Station Blueprint (600 RP) [requires: Shipyard Basics] ← Phase 2
            Unlocks: Orbital Station building
            Unlocks: Remote mining of Gas Giants and Ice Giants

Branch 6 — Defence¶

Audited 2026-08-30. ~~Correct against current design. Reinforced Wall and Heavy Turret are distinct buildings rather than Mk levels, so they are legitimate research unlocks.~~

⚠️ That defence is withdrawn. Amended 2026-09-06 (OI-361) — see §0.5. All buildings tier by upgrade kit, so Reinforced Wall and Heavy Turret are Mk levels, not research unlocks. The two nodes that unlocked them now unlock ammunition instead. The rest of the branch is unchanged and its 2026-08-30 audit still stands.

Unlocks turrets, walls, alien countermeasures, and radar systems.

Cost curve: 60 → 120 → 240 → 480 RP (medium, steady doubling)

[START]
    │
    ├── Basic Fortification (60 RP)
    │       Unlocks: Wall building
    │       Unlocks: Gate building
    │       └── Advanced Fortification (180 RP)
    │               Unlocks: Gate automation (opens/closes on native proximity)
    │               (Reinforced Wall removed — a wall reaches higher HP by upgrade kit)
    │
    ├── Basic Turret (60 RP)
    │       Unlocks: Turret building
    │       Unlocks: Metal Plate ammunition — the first rung of the ladder
    │       └── Turret Upgrade I (150 RP)
    │               Effect: Turret range +30%, fire rate +20% (flat, on the building)
    │               └── Turret Upgrade II (300 RP) [requires: Advanced Fortification]
    │                       Unlocks: Hull Plating ammunition — rung two
    │                       Requires a Turret at Machine Mk2 to chamber it
    │                       (Heavy Turret removed — a turret reaches 2x2 and higher
    │                        rate by upgrade kit, in place, keeping its modules)
    │
    ├── Alien Radar (80 RP)
    │       Unlocks: Radar building (shows alien movement on minimap)
    │       └── Deep Radar (200 RP)
    │               Effect: Radar range doubled, shows alien tier indicators
    │
    ├── Unit Spawner (120 RP) [requires: Basic Turret, Basic Fortification]
    │       Unlocks: Unit Spawner building (produces defence bots)
    │       └── Elite Unit Spawner (400 RP) [requires: Turret Upgrade I]
    │               Unlocks: Elite Defence Bot (higher HP, ranged attack)
    │
    └── Alien Analysis (100 RP) [requires: Alien Radar]
            Effect: Alien HP and attack values shown in radar overlay
            └── Countermeasures (300 RP)
                    Unlocks: EMP Emitter building (stuns alien groups, power cost)

⚡ INFINITE NODE — Combat Doctrine
    Prerequisite: Elite Unit Spawner
    Effect: +3% turret damage AND +2% alien resistance per level
    See: Infinite Level Nodes section

Branch 7 — Genesis Abilities¶

Audited 2026-08-30. Correct at the time, plus Bot Programming I and II added (OI-322).

⚠️ Amended 2026-09-07 (OI-369) — see §0.6. Seven flat-percentage nodes deleted. Genesis speed, mining rate, carry capacity and queue depth are now bought with upgrade kits and modules, not research, per [40_Genesis Design](<../Systems/40_Genesis Design.md>) §6. The branch keeps everything that unlocks a verb, which is what a research tree is for.

Unlocks new Genesis tasks and expands automation. It no longer sells speed.

Cost curve: 50 → 100 → 200 → 400 RP (low early — Genesis is central to gameplay)

[START]
    │
    ├── (Genesis Build Speed I / II — DELETED. Machine Mk buys build speed)
    │
    ├── Genesis Multi-Resource Task (75 RP)
    │       Unlocks: Genesis can mine multiple resource types per task
    │       (was "Genesis Mining Upgrade"; the +30% speed is gone, Machine Mk buys it)
    │
    ├── Genesis Task Priority (100 RP)
    │       Unlocks: Task priority reordering UI (drag to reorder)
    │       Unlocks: Repeat task toggle (loop a task indefinitely)
    │       (Queue Expansion DELETED — Mk buys queue depth.
    │        Bulk Mining DELETED — a Productivity module buys carry)
    │
    ├── Genesis Repair (100 RP)
    │       Unlocks: Genesis can repair damaged buildings
    │       (task: REPAIR_BUILDING — Genesis flies to building, restores HP)
    │       └── Genesis Auto-Repair (300 RP)
    │               Unlocks: Auto-repair mode — Genesis automatically repairs
    │               buildings below 50% HP when task queue is empty
    │
    ├── Genesis Demolish (75 RP)
    │       Unlocks: Genesis can demolish buildings
    │       (task: DEMOLISH_BUILDING — returns partial resources)
    │
    ├── Bot Programming I (100 RP)
    │       Unlocks: Genesis automation — queued tasks run without per-task input
    │       └── Bot Programming II (300 RP)
    │               Unlocks: Construction Bot Bay building
    │               Unlocks: Construction Bots, which build from the shared queue
    │
    ├── Genesis Blueprint Execution (150 RP) [requires: Blueprint System — M3.5]
    │       Unlocks: Genesis can execute blueprint stamps autonomously
    │       (task: EXECUTE_BLUEPRINT — Genesis builds entire stamped area)
    │
    └── Genesis Level Transition (200 RP) [requires: Basic Excavation or Basic Construction]
            Effect: Genesis teleport range includes all unlocked vertical levels
            Unlocks: Level-aware task assignment (assign tasks on any level)

⚡ INFINITE NODE — Genesis Optimisation
    Prerequisite: Genesis Bulk Mining
    Effect: +2% Genesis build speed AND +2% mine speed per level
    See: Infinite Level Nodes section

Branch 8 — Modules¶

Audited 2026-08-30. Already reconciled and correct — it is the one branch that had been maintained, and its Removed from this branch table below is why. One naming conflict found and not resolved here: this branch and [24_Module System Design](<../Systems/24_Module System Design.md>) call the module a Power Pole, while [25_Power System Design](<../Systems/25_Power System Design.md>) §8 says it is "no longer a 'roof-mounted pole'" but a range extender on the integrated transmitter. The mechanism agrees in both; only the name does not. The module document is the stated authority, so its name is kept here. Tracked as OI-323.

Unlocks module capability. Module slots are not researched — slot count comes from footprint size plus Machine Mk.

Authority: [24_Module System Design](<../Systems/24_Module System Design.md>) §2.2, §3, §3.1, §3.2. Where the two disagree, that document wins.

Cost curve: 80 → 160 → 320 → 640 RP (medium — meaningful investment per unlock)

[START]
    │
    └── Module Crafting (80 RP)
            Unlocks: Module Crafter building
            Unlocks: Efficiency Module recipe
            Unlocks: the four Upgrade Kit recipes
                     (Base Mk2/Mk3, Machine Mk2/Mk3)
            │
            └── Module Technology I (160 RP)
                    Unlocks: Roof-Mounted Power Pole module
                    │
                    └── Module Technology II (320 RP)
                            Unlocks: Status Module (detailed + remote readout)
                            │
                            └── Module Technology III (640 RP)
                                    Unlocks: Productivity Module

⚡ INFINITE NODE — Module Amplification
    Prerequisite: Module Technology III
    Effect: +1.5% to all module effects per level (diminishing returns above level 30)
    See: Infinite Level Nodes section

Efficiency unlocks with Module Crafting itself, not with any capability node. The system and one usable module arrive together, so roof slots are never left visibly empty with nothing that could fill them, and the branch never dumps a whole system on the player at once. The Module Crafter is deliberately not free from the start, because it also produces the four Upgrade Kits and an unresearched Crafter would make Mk3 upgrades available in the first hour. See [24_Module System Design](<../Systems/24_Module System Design.md>) §3.1.

Ordering is convenience → comprehension → power. The roof pole is a spatial upgrade, Status is telemetry, Productivity is the genuine prize and belongs last.

Removed from this branch¶

Removed	Why
Module Slot Expansion I / II / III	Slots are not researched. Count comes from footprint size class plus Machine Mk, range 1 to 6.
Quality, Power and Capacity Modules	Not in the module set. The four types are Efficiency, Power Pole, Status, Productivity.
Module Tier 2 / Tier 3 Crafting	Whether modules have Mk tiers of their own is OPEN; the recommendation is flat for Phase 1.
Combination Research	There are no combination bonuses. They were a property of the stacking model, where order and adjacency created the emergence. With fixed independent slots there is no adjacency to build on.
Speed Module	Not in the module set. Whether it exists at all is OPEN — it may overlap Productivity too heavily.

Branch 9 — Environmental¶

Written 2026-08-30 against [26_Pollution, Waste & Organic Systems Design](<../Systems/26_Pollution, Waste & Organic Systems Design.md>) and [27_Organic Farming & Biomass Design](<../Systems/27_Organic Farming & Biomass Design.md>) (OI-006, OI-248).

Unlocks waste treatment, emissions control, remediation and cultivation.

Cost curve: 100 → 200 → 400 RP. Modest, because the branch is optional and buys no throughput.

[START]
    │
    ├── Waste Handling (100 RP)
    │       Unlocks: Dump and Discharge — the cheap, dirty answer
    │       Unlocks: solid waste and contaminated water as storable substances
    │       │        in Silo and Tank
    │       │        ← Nuclear Fission (Branch 2) requires this node
    │       └── Waste Reprocessing (300 RP) [requires: Power Management — Branch 2]
    │               Unlocks: Recycler building
    │               Unlocks: Water Treatment plant
    │
    ├── Emissions Control (200 RP) [requires: Power Management — Branch 2]
    │       Unlocks: Air Scrubber building
    │       └── Incineration (300 RP)
    │               Unlocks: Incinerator building, with partial heat recovery
    │
    ├── Cultivation (150 RP)
    │       Unlocks: Biomass Farm — Control Hut plus Greenhouse Bays
    │       └── Aquaculture (250 RP) [requires: Fluid Extraction — Branch 1]
    │               Unlocks: Algae Farm — Pond Head plus Pond Bays
    │
    └── Land Remediation (400 RP) [requires: Waste Reprocessing]
            Unlocks: Soil Remediation building

Why the branch exists, and why it is optional¶

Pollution is a consequence system: produced by power, by production and by disposal, and cleaned up by buildings that make nothing. Folding these into Industrial would hand a player the cleanup as a side effect of expanding. A separate branch makes cleaning up a choice that costs RP and buys no throughput, which only works if the two are separable.

Nothing here gates production. A player may take none of it and live with the pollution.

Two cross-branch dependencies, pointing opposite ways¶

This branch and Branch 2 are deliberately interlocked, and each direction is argued in its own document.

Direction	Rule	Why
Branch 9 → Branch 2	Waste Reprocessing and Emissions Control both require Power Management	`26_Pollution` §5: "the clean answer always costs electricity, so a player choosing it must first solve generation." The Recycler, Water Treatment and Air Scrubber all draw significant power
Branch 2 → Branch 9	Nuclear Fission requires Waste Handling	`25_Power System Design` §5.1: a reactor produces waste that must be stored. Unlocking 600 PU with no way to handle its output makes waste a surprise rather than a cost

Waste Handling is the light gate on purpose. At 100 RP it is not there to make nuclear expensive — nuclear is already 800 RP with a uranium chain and a continuous coolant pipe. It is there to make waste impossible to be surprised by: the player must have unlocked somewhere to put it before they can build the thing that makes it. Sequence, not cost.

The three waste choices are all reachable¶

26_Pollution §5 gives store, treat, or dump as three valid answers with different costs, and the branch preserves that rather than making treatment the correct one:

Store needs no research at all — Silo and Tank are basic buildings
Dump arrives at the first node, cheaply, exactly as its "nearly free, but ground contamination" framing intends
Treat is the deep and expensive path, and it is gated behind power because it costs power

The player who takes Waste Handling and stops has made a real choice, not a partial one.

Farming sits here rather than in Industrial¶

Cultivation feeds the organic chain that remediation and biomass power both draw on, and 27_Organic Farming & Biomass Design builds both families from one Control Hut plus Bays pattern. Bays are extensions rather than separate buildings, so one node unlocks the whole family.

Aquaculture requires Fluid Extraction because a Pond Head is a water building.

Cross-Branch Prerequisites¶

Some powerful nodes require research from multiple branches. These are the most impactful unlocks in the game.

Node	Requires	Unlocks
Advanced Assembly	Industrial: Component Assembly + Industrial: Chemical Processing	Advanced Assembly building
Power Conduit	Vertical: Basic Excavation + Power: Power Grid Expansion	Cross-level power distribution
Sky Pipeline	Vertical: Pipe Pump + Vertical: Basic Construction	Vertical pipes between sky levels
Core Excavation	Vertical: Advanced Boring + Power: Deep Core Tap II	Underground Level 4
Orbital Station Blueprint	Exploration: Shipyard Basics + Vertical: Basic Construction	Orbital stations above Gas/Ice Giants
Genesis Blueprint Execution	Genesis: Genesis Task Queue Expansion + M3.5 Blueprint System	Full blueprint automation
Fuel Power	Power: Coal Firing + Industrial: Fluid Extraction	Fuel Generator — the first generator needing a pipe
Wind Power	Power branch + Vertical: Basic Construction	Wind Turbine, whose output scales with altitude
Nuclear Fission	Power: Fuel Power + Environmental: Waste Handling	Nuclear Reactor. A reactor cannot be unlocked before somewhere to put its waste
Waste Reprocessing	Environmental: Waste Handling + Power: Power Management	Recycler and Water Treatment. Treatment costs power, so generation comes first
Emissions Control	Environmental branch + Power: Power Management	Air Scrubber, for the same reason
Aquaculture	Environmental: Cultivation + Industrial: Fluid Extraction	Algae Farm — a Pond Head is a water building

Branch 2 and Branch 9 are interlocked in both directions, which is deliberate. Cleaning up costs electricity, so Environmental leans on Power; and the dirtiest generator in the game may not be unlocked before the means to handle its waste, so Power leans back. Neither branch is mandatory, but the nuclear path and the clean path each require the other's groundwork.

RP Cost Reference¶

Branch	Cheapest Node	Most Expensive Finite Node	Rough Full-Branch Cost	Infinite Node
Industrial	50 RP	800 RP	~3,500 RP	Deep Extraction
Power	50 RP	1,200 RP	~5,400 RP	—
Research & Science	40 RP	500 RP	~2,000 RP	Research Acceleration
Vertical Expansion	100 RP	1,000 RP	~6,000 RP	—
Exploration	100 RP	1,200 RP	~5,500 RP	—
Defence	60 RP	480 RP	~2,500 RP	Combat Doctrine
Genesis Abilities	50 RP	400 RP	~2,400 RP	Genesis Optimisation
Modules	80 RP	640 RP	~3,500 RP	Module Amplification
Environmental	100 RP	400 RP	~1,700 RP	—
Total finite nodes			~32,500 RP
Supply Chain Mastery		2,000 RP	Full tree completion reward	—

Completing all finite nodes (~32,500 RP total) unlocks the Full Tree Bonus (+25% supply chain contribution) and the Supply Chain Mastery node. A normal 8 to 10 hours of play typically covers 30 to 50% of the finite tree, leaving the infinite nodes as long-term goals.

Science Drive Production Chain¶

Drive	Recipe	Unlocks	RP per Drive
`sci_basic_drive`	Metal Plates × 2 + Circuit Board × 1	Shallow nodes — most of the tree	10 RP
`sci_advanced_drive`	Power Cells × 1 + Silicon Wafers × 2 + Polymer × 1	Deep nodes	50 RP
`sci_quantum_drive`	Quantum Processor × 1 + Energy Conduit × 1	Endgame nodes	250 RP

Passive Field Data rate: approximately 1 RP per 10 ticks per running building at base rate (upgradeable via Field Data Collection nodes).

Implementation Notes¶

ResearchNodeDefinition Resource¶

# ResearchNodeDefinition.gd
class_name ResearchNodeDefinition
extends Resource

@export var id: String
@export var display_name: String
@export var description: String
@export var branch: String           # "industrial" | "power" | "research" etc.
@export var rp_cost: int
@export var prerequisites: Array[String]  # array of node IDs required before this unlocks
@export var unlocks_buildings: Array[String]
@export var unlocks_recipes: Array[String]
@export var unlocks_flags: Array[String]  # e.g. "underground_level_1", "sky_level_1"
@export var effect_description: String    # human-readable effect summary
@export var icon: Texture2D

ResearchManager Autoload¶

# ResearchManager.gd (autoload)
var researched_nodes: Array[String] = []     # world-scoped — resets only in a new world
var active_research: Array[String] = []      # currently researching (max 1–3)
var paused_research: Dictionary = {}         # { "node_id": rp_invested } — paused nodes preserve progress
var rp_pool: float = 0.0
var max_concurrent_slots: int = 1            # increases via Research Expansion nodes

func is_available(node_id: String) -> bool:
    var node = _get_node(node_id)
    return node.prerequisites.all(func(p): return p in researched_nodes)

func is_researched(node_id: String) -> bool:
    return node_id in researched_nodes

func start_research(node_id: String) -> void:
    assert(active_research.size() < max_concurrent_slots)
    assert(is_available(node_id))
    active_research.append(node_id)

func pause_research(node_id: String) -> void:
    # Preserves invested RP — node holds progress indefinitely
    assert(node_id in active_research)
    active_research.erase(node_id)
    if node_id not in paused_research:
        paused_research[node_id] = 0
    # rp already tracked in progress dict

func resume_research(node_id: String) -> void:
    assert(active_research.size() < max_concurrent_slots)
    assert(node_id in paused_research)
    active_research.append(node_id)
    paused_research.erase(node_id)

func get_estimated_completion_time(node_id: String) -> float:
    # Returns estimated ticks to complete based on current RP rate
    var node = _get_node(node_id)
    var rp_remaining = node.rp_cost - _get_progress(node_id)
    var current_rp_rate = _get_current_rp_rate()  # RP per tick
    if current_rp_rate <= 0:
        return INF
    return rp_remaining / current_rp_rate

func tick_research(delta_rp: float) -> void:
    # Distribute incoming RP evenly across active_research slots
    # When a node completes, apply all unlocks and fire signal
    pass

Full Tree Completion Bonus¶

When a player researches every finite node in every branch, two things happen:

1. Flat Supply Chain Contribution Bonus A permanent +25% supply chain contribution multiplier for the remainder of the world. This stacks with all other contribution factors (pipe complexity, planet type, core depth, etc.).

2. Supply Chain Mastery Node Unlocked A special cross-branch node becomes available — Supply Chain Mastery — the only node specifically designed to increase supply chain contribution directly. It sits outside all 8 branches as a capstone node.

Supply Chain Mastery (unlocks after all finite nodes complete)
├── Cost: 2,000 RP
├── Prerequisite: All finite research nodes completed
├── Effect: +10% supply chain contribution permanently (this world)
└── Note: This is the only node whose sole purpose is contribution bonus

The full tree bonus rewards players who commit to total mastery. It is not required for effective play — most players will never reach it in a single world. It is the reward for the most dedicated worlds.

Infinite Level Nodes¶

Six branches contain one Infinite Level node each. These nodes have no upper bound — they can be researched indefinitely, each level providing a compounding multiplier bonus. Cost scales logarithmically: large jumps early, slowing to a steady grind at high levels.

Cost Formula¶

cost(level) = base_cost × (1 + log10(level) × scale_factor)

Example — Research Acceleration at level 10:
cost = 200 × (1 + log10(10) × 3.0) = 200 × 4.0 = 800 RP

At level 100:
cost = 200 × (1 + log10(100) × 3.0) = 200 × 7.0 = 1,400 RP

At level 1000:
cost = 200 × (1 + log10(1000) × 3.0) = 200 × 10.0 = 2,000 RP

Cost increases meaningfully at first but levels off — a level 1000 node costs only 2.5× a level 1 node. Long-term grind remains accessible.

Bonus Formula¶

bonus(level) = base_bonus × level × diminishing_factor

Where diminishing_factor = 1 / (1 + level × 0.01)
This means early levels give near-full bonus, very high levels give reduced per-level gain.

Infinite Level Node Definitions¶

🔬 Research Acceleration (Research & Science branch)¶

Prerequisite: Research Expansion II (3rd concurrent slot) Base cost: 200 RP · Scale factor: 3.0 Effect per level: +2% passive RP generation rate (diminishing returns above level 50)

Level	RP Cost	Cumulative Bonus
1	200 RP	+2% RP rate
5	340 RP	+9.5% RP rate
10	800 RP	+18% RP rate
25	1,000 RP	+40% RP rate
50	1,140 RP	+67% RP rate
100	1,400 RP	+95% RP rate

⚔️ Combat Doctrine (Defence branch)¶

Prerequisite: Elite Unit Spawner Base cost: 300 RP · Scale factor: 3.0 Effect per level: +3% turret damage AND +2% alien damage resistance (both apply)

Level	RP Cost	Turret Damage	Alien Resistance
1	300 RP	+3%	+2%
10	1,200 RP	+27%	+18%
25	1,500 RP	+60%	+40%
50	1,710 RP	+100%	+67%

🤖 Genesis Optimisation (Genesis Abilities branch)¶

Prerequisite: Genesis Bulk Mining Base cost: 150 RP · Scale factor: 2.5 Effect per level: +2% Genesis build speed AND +2% Genesis mine speed

Level	RP Cost	Build Speed	Mine Speed
1	150 RP	+2%	+2%
10	525 RP	+18%	+18%
25	694 RP	+40%	+40%
50	806 RP	+67%	+67%

⚙️ Module Amplification (Modules branch)¶

Prerequisite: Module Technology III Base cost: 400 RP · Scale factor: 3.5 Effect per level: +1.5% to all module effects (diminishing returns above level 30)

Level	RP Cost	Module Effect Bonus
1	400 RP	+1.5%
10	2,000 RP	+13%
25	2,600 RP	+28%
50	3,100 RP	+42%

Deliberately slower scaling than other infinite nodes — modules are already very powerful at high levels.

⛏️ Deep Extraction (Industrial branch)¶

Prerequisite: Belt Upgrade II + Fluid Extraction Base cost: 175 RP · Scale factor: 2.5 Effect per level: +2% extraction rate on all mining/harvesting/pumping buildings

Level	RP Cost	Extraction Rate Bonus
1	175 RP	+2%
10	613 RP	+18%
25	809 RP	+40%
50	940 RP	+67%
100	1,138 RP	+95%

Infinite Node Summary¶

Node	Branch	Prerequisite	Base Cost	Effect
Research Acceleration	Research & Science	Research Expansion II	200 RP	+2% RP rate/level
Combat Doctrine	Defence	Elite Unit Spawner	300 RP	+3% turret dmg + 2% alien resist/level
Genesis Optimisation	Genesis Abilities	Genesis Bulk Mining	150 RP	+2% build + mine speed/level
Module Amplification	Modules	Module Technology III	400 RP	+1.5% module effects/level
Deep Extraction	Industrial	Belt Upgrade II + Fluid Extraction	175 RP	+2% extraction rate/level

GDScript — Infinite Node Implementation¶

# ResearchNodeDefinition.gd addition
@export var is_infinite: bool = false
@export var infinite_base_cost: int = 0
@export var infinite_scale_factor: float = 3.0
@export var infinite_base_bonus: float = 0.02
@export var infinite_diminishing_threshold: int = 50  # level where DR kicks in

func cost_at_level(level: int) -> int:
    if not is_infinite:
        return rp_cost
    return int(infinite_base_cost * (1.0 + log(level) / log(10) * infinite_scale_factor))

func bonus_at_level(level: int) -> float:
    var diminishing = 1.0 / (1.0 + level * 0.01)
    return infinite_base_bonus * level * diminishing

# ResearchManager.gd addition
var infinite_node_levels: Dictionary = {}  # { "node_id": current_level }

func get_infinite_level(node_id: String) -> int:
    return infinite_node_levels.get(node_id, 0)

func complete_infinite_level(node_id: String) -> void:
    infinite_node_levels[node_id] = get_infinite_level(node_id) + 1
    _apply_infinite_bonus(node_id)

Open items for this document are tracked in docs/open-items.md, area research.

Revision History¶

Version	Date	Changes
0.1	2026-02-27	Initial document — 8 branches, full node tree, cross-branch prerequisites, RP cost reference, Science Drive chain, ResearchNodeDefinition resource, ResearchManager autoload
0.2	2026-02-27	Full Tree Completion Bonus, infinite level nodes (5 branches), logarithmic cost formula, GDScript for infinite nodes
0.3	2026-02-28	All open questions resolved — pause/resume research (no cancellation, RP preserved), shared slot pool in multiplayer, no base tree mutual exclusion (faction research only), estimated completion time shown in UI, Field Data scales on both building count (base) and throughput (bonus). ResearchManager updated with pause/resume and estimated time methods.
0.4	2026-08-29	Branch 4 rewritten off the generic Shaft. Unlocks: Shaft building removed from Basic Excavation, since no such building exists; Vertical Lift and Pipe Pump now unlock the Item Lift and Fluid Riser structures directly. The Power Conduit node already existed and needed no change. Branch summary and header now say vertical structures. (OI-013)
0.4	2026-08-30	§0 Reconciliation Status added (OI-242): this document is the single authority for the tree, and it is amended in place rather than rebuilt - the model is current and only branch contents are stale. Records that `04_Factory`'s competing tier-gated listing was deleted, since this tree forbids tier gates. Branch 9, Environmental added (OI-006): waste, remediation and farming get their own optional branch, the three new generators go to Branch 2, and the Nuclear Reactor takes a cross-branch prerequisite on a waste-handling node - the only thing Branch 9 gates. Contents and RP costs remain with OI-248 and OI-245.
0.5	2026-08-30	The reconciliation pass §0 called for, done in one go. Branch 2 rebuilt (OI-025, OI-244, OI-245, OI-087): three Mk-gating nodes deleted as unbuildable, replaced by a real generator ladder and by Energy Storage; Biomass, Coal, Wind and Nuclear given nodes; transmission added at last, MV and HV, extending Branch 2 rather than taking its own branch. Branch 9 written in full (OI-248), seven nodes, with two cross-branch dependencies pointing opposite ways between it and Power. Power Management and Bot Programming I/II added (OI-322). All six remaining branches audited and dated (OI-246); Science Drive rows reworded off tier language. RP Cost Reference updated throughout — the finite tree moves from ~29,000 to ~32,500 RP. Raised OI-323 for the power module's name.
0.8	2026-09-07	§0.6 amendment, Branch 7 (OI-369). Research stops selling speed. Genesis upgrades by three mechanisms — research for verbs, upgrade kits for Mk, modules for capacity — so four flat-percentage nodes are deleted (Build Speed I and II, the speed half of Mining Upgrade, Bulk Mining, Queue Expansion). Mining Upgrade's unlock half survives as Genesis Multi-Resource Task. Everything that unlocks a verb is kept, as is the Genesis Optimisation infinite node. Branch RP total needs recomputing.
0.7	2026-09-06	§0.5 amendment, Branch 6 (OI-361). All buildings tier by upgrade kit, so Reinforced Wall and Heavy Turret are Mk levels, not research unlocks, and the 2026-08-30 audit note defending them is withdrawn. Advanced Fortification now unlocks gate automation only; Turret Upgrade II unlocks Hull Plating ammunition, requiring a Turret at Machine Mk2 to chamber. What a rung does recorded (OI-362): rate of fire, range and spread, never damage — so nothing goes obsolete, every rung raises consumption, and range and spread change turret placement rather than turret count. Turret Upgrade I and Combat Doctrine unaffected. No other branch touched.
0.6	2026-09-05	§0.4 amendment. Research corrected from session-scoped to world-scoped throughout, per the vocabulary locked in `04_Data Dictionary` §0 — the model was always right, the word was wrong in a way that would have been implemented literally. The second tree recorded: Engineering Research is account-scoped, flat, and owned by `35_Economy Design`; this document owns Factory Research only. Infinite Level nodes explicitly stay here and stay world-scoped, correcting an earlier suggestion that they move. Research Point sources unchanged, and contribution confirmed not to feed them. No branch listing touched.