Assasins Creed Unity was the one that failed, I played it at my friends house and his decent computer got a maximum of 15 fps on lowest settings, one time I got 6 fps. Also there are quite a few bugs and gameplay wise is better than AC3 but not as good as Black Flag. The 2 mediocre ones were Watch Dogs which was supposed to be revolutionary but ended up being okay at best, and the crew which apparently has very little activity variety so you will only be doing a combination of about 3 activities. Then there is Far Cry 4, which has barely even changed from Far Cry 3, but I heard that despite this it is pretty good as Far Cry 3 was a good game.