every time u get a checkpoint to save and quit and if you die to go to the dashboard and go back to the game. You will start at your checkpoint with your death count reset to zero making the achievement "that just happened", much easier. Stop watching the speed runs and other videos and just follow this simple trick!
I'm not trolling I'm dead serious I've tried it myself earlier
[Edited on 11.24.2011 10:15 PM PST]
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I recently did The Library on Legendary died 4 times before I got past the first checkpoint then comnpleted the rest of the level with out dying once.