did you have an enemy (monster) army/unit selected when you pressed end turn? game seems to crash consistently (at least on my machine) when i press end turn while a hostile army is selected.

I had this same issue, for some reason my game kept crashing on random turns, and it would always crash on that turn, regardless of what I did.

I have a thread about this on the Steam forums as well. Since I was having the issue I figured out a way to fix it, which worked for me.

Simply have your steam re check the files of your game. If you dont know how to do this:

Go to your steam library -> Right click Fallen Enchantress: Legendary Heroes -> Go to Properties -> Local Files -> Verify Integrity of game cache

If you dont have steam well.. Idk..