Well my question is all in the title. I just wanted to know why exactly because I think it's weird that if you enter cheats into the game. That they'll be able to prevent a couple of achievements from being unlocked. It sucks, you know, it really does.
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Because if you can't beat the game without cheats, one does not deserve the achievements.
You gain achievements through accomplishing things throughout the game; once you cheat you're unable to accomplish (:
The whole point of achievements is doing something without cheats. Everyone would have 34928340983203 gamerscore if you could get them with cheats. Deal with it, or don't play.
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