As we all know there is a glitch to beat the game on X-tream (hard):
If you beat the game on New Mutant (easy) then select X-tream when starting a new game + you can quit out and use level select to the last level. It will now be on X-tream. Beat the level for the achievement.
If you mess up and do not choose X-tream when ask at the start of new game + YOU MUST replay the entire game.
- Changing the difficulty, hitting a checkpoint, and then loading the last level will not give you the achievement.
- Beating the last level again will not let you pick new game + again.
- If you choose X-tream on new game + then changed it to a lower difficulty for whatever reason, it has saved and your screwed. Changing back will not give you the achievement.
I like many others now have to play the game again. It is not long but it wasn't something I wanna play again. I have seen this discussed in two or three threads now and hopefully this will sum it all up and save people from playing the game twice in the future.