Ok did everything with the DLC, the cache, whatever, nothing. I hate these glitchy achievements.
Ok well for those wondering, the best thing would be to redo a run in easy, having vita chambers turned off (on on, haha), and go through the game as quickly as possible. It took me 4h15 from "new game" to "achievement unlocked", I rushed and was low on ammo at some time but all in all, as long as you have 80 electric gel for the boss, it's gonna be easy.
Last edited by Lordji; 09-13-2012 at 11:36 PM.