General Raam on Insane- I had to use a glitch for that bastard. The section of the Ares battle in GOW where you defend your family from the swarm of Kratos clones, that was just on Hard. I literally do not understand how that can be done on God mode. Azazel in Tekken 6 was a cheap boss- Jinpachi in T 5 was nothing compared to that.
Games these days are generally easy, so I don't know what else.