Devil May Cry 4

Beat up to and including level 101 in Bloody Palace mode. To unlock Bloody Palace mode, beat the game on Devil Hunter difficulty. Do not quite the game, you need to die or finish all 101 floors to get the achievement. Below are a list of the enemies from waves 91-101:

91 Faust x3
92 Alto Angelo x3, Bianco Angelo x4
93 Assault x8
94 Chimera x3, Chimera Seed x6, Bianco Angelo x2
95 Basilisk x16, Chimera Seed x4
96 Gladius x8, Cutlass x3, Bianco Angelo x3
97 Mephisto x6, Mega Scarecrow x2
98 Chimera x4, Chimera Seed x3
99 Alto Angelo x2, Bianco Angelo x44
100 Angelo Agnus (Boss)
101 Dante (Boss)

Thanks to xbox360achievements.org for the list. Great site and worth visiting.

There is a very simple process to do this, but only as Nero. And I didnt even use super.

Nero has a useful ability to jump into the air, and stay aloft almost endlessly. When in the air, use his demon arm to grab enemies, pull them to you, and begins hacking away. you stay hovering as long as you are striking, and you can pull them to you from great distance. I even beat Dante in this manner.