Coop Mod — They Are Billions

The game’s engine was built specifically for single-player management, handling the pathfinding and logic for roughly 20,000 units simultaneously. This technical hurdle was the developer's primary reason for not including multiplayer at launch. However, dedicated modders have circumvented these limitations to create a functional, albeit imperfect, cooperative experience.

| Challenge | Potential Solution | |-----------|--------------------| | Game engine (Unity) originally single‑player | Use or dedicated relay server ; freeze simulation ticks via deterministic lockstep | | Pathfinding with multiple colonies | Reuse existing pathfinding; split calculations per player region | | Desync risks | Periodic checksum sync; rollback on mismatch | | Save/Load co-op | Store all player states in one save file; host controls load | | UI scaling | Add player color coding (blue, green, yellow, purple) | they are billions coop mod

The Co-op mod significantly alters the gameplay experience of "They Are Billions," offering several benefits: The game’s engine was built specifically for single-player

While the developers at Numantian Games have focused on the single-player experience and the campaign mode, the modding community has provided an answer. Here is everything you need to know about the unofficial Cooperative Mod for They Are Billions . they are billions coop mod

Because this is an unofficial mod, it requires a few extra steps to get running compared to a standard Steam Workshop subscription.