MODDING IS FULLY ON, but be warned, the architecture is still very new and experimental, expect and please reports bugs and questions to the Discord
Mods can now ship C# content: add new nodes, traits (culture/religion effects), AI behavior (personality rules, civilization properties, telling SmartAI to fund new nodes, or a full custom AI), and alerts, or replace, patch, and disable vanilla nodes. Mod source is compiled and security-checked when the game loads it. A ready-to-copy Template mod and examples are in StreamingAssets/Mods/Examples/. Installed mods show up in the Workshop window next to your maps and scenarios, where you can turn each one on or off. The window opens as a mod manager even with Steam offline, so you can enable, disable, and reorder your mods, then use the Restart Game button that lights up when your changes need a relaunch to take effect. Mods can also patch the map, retune balance rules through gamerules.json, and add or replace music, all covered in the modding guide
Builds now include the base game's main content as readable C# in StreamingAssets/Mods/Reference/, so you can see exactly what a node does before replacing, patching it or to simply observe the game internal logic
AI civilizations now pick culture and religion traits that fit their current situation and personality
Switching scenarios in the new game menu no longer resets your game setup
Fix Pillage raids pillaging the wrong civ
Fix the Rare Ceramics, Glass, Textile and Wine traits producing far more than intended
Fix several trait spawn conditions (Coast Aversion, Amazing Foragers, Justiciars)
Fix some silent bugs (like save/load might break the horse spread)