The tech tree is built around one shared backbone all 10 cultures climb, plus culture-specific capstones in the Empire Age. The shared backbone has 10 branches; each culture's per-culture tree is the same backbone with two unique capstone nodes spliced on.
Per-culture trees. Each culture's full diagram (Mermaid) lives on its own page. See: Fjordborn · Sun Dune · River Crown · Jade Lotus · Ironpeak · Azure Isles · Cairnveil · Condor Crown · Red Earth · Thunder Lodge.
The tree is divided into four eras (also called "ages" or epochs):
| Era | Name | Notes |
|---|---|---|
| I | Settlement Age | Starter techs. Roads, basic militia, fletching, signal fires, scouting, sky-watching, sacred offerings. |
| II | City-State Age | Discipline, mail/lamellar, riding harness, bloomery furnaces, organized priesthood, hull bracing, insulated stores. |
| III | Kingdom Age | Veteran companies, siege corps, formation doctrine, naval logistics, militant cult, written law, cartography. |
| IV | Empire Age | Imperial bureaucracy, divine legitimacy, oracle sanction, sphere of influence, rapid assault, defensive depth — plus two culture-specific capstones. |
Each era unlocks new buildings and units. Cultures can technically reach the Empire Age, but their capstones are unique.
The shared backbone splits into 10 branches; each branch follows its own chain through eras:
Research is gated by buildings. Tier-1 buildings unlock Era I research; tier-3+ unlock Era IV. Common buildings:
A culture's research speed depends on:
Each culture has two empire-age capstones unique to it. Mechanically, these are typically:
| Culture | Capstones |
|---|---|
| Fjordborn Clans | Sea-Wolf Oaths · Winter Stores of Eira |
| Sun Dune Sultanates | Camel Corps Oaths · Oasis Rites |
| River Crown Kingdoms | Flood Wardens · Royal Scribes |
| Jade Lotus Empire | Imperial Mandate · Celestial Observatory |
| Ironpeak Holds | Deep Mines Network · Sulfur-Charge Engineering |
| Azure Isles League | Storm Reading · Koru Wind-Sailor |
| Cairnveil Tuatha | Omen Gathering · Druid Circle |
| Condor Crown Confederacy | Signal Fire Network · Cloud Temples |
| Red Earth Covenant | Great Drumnet · Griot Legitimacy |
| Thunder Lodge Confederacy | Shared Stores · Adoption Network |
You don't have to research everything. The branch system means:
Branches are a strategic identity choice, not a "tech everything" track.
Research throughput compounds from:
technology.md (canonical) and rts_research_tree_design_table.xlsx (balance).Sources: technology.md, rts_research_tree_design_table.xlsx, per-culture _divers/<culture>_tech_tree.mmd files.