Acrocalypse Now

 Acrocalypse Now  is a Cataclysm heroic dungeon achievement needed for the Glory of the Cataclysm Hero achievement, rewarding the.

Strategy
The Crocolisks spawn in waves of 4, so you need to await at least 5 waves to get them all together. They stack a bleed debuff when they hit a target, so having them kited is nearly a must.

Trivia
The achievement name is a obvious reference to "Apocalypse Now".