For example, Hakuoro. In game, he is kind of mysterious since he was so war intelligent. In anime, he is more like braindead idiot who acts on a whim.
Example: In game he plots the night ambush attack to the fort. Kill guards silently and open the gate so others can rush in.
And what does he do in anime? They charge OUTSIDE the fort with screaming RAAHH or something. Just what the hell? What is the point of whole plot if you going to let the enemy know "hey we are comming" when you are in totally disadvantageous situation (outside). Yeah.. Villagers without no real equipment can take a fort that way..