Well, basically you can change almost everything as long as you doesn´t forget to change related stuff too. Check the FAQ and guides to modding in this forum.Originally Posted by [b
Changing your, or other factions, behaviour will have a significant impact on the game. Ex: I grew tired of France stampeding through Europe and HRE falling apart in every other game so I simply changed "catholic expansionist crusader" to "catholic defensive crusader" and 9 out of 10 games it runs as I want it. I also changed the Eggys to "Devoutee" since I don´t find it appealing to find them in the Balkans after a massive blitz on the Turks and Byz.
Good luck
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