Ok, so this is one of the most difficult and long achievements that rivals the likes of 7 day survivor from Dead Rising and Seriously 3.0 from Gears of War 3. It requires you to press RT maybe 20-25 times plus you must move with the left stick although I found it rather effective to use both left stick and left trigger at the same time. It makes it so you can move at a rather quick pace that will lead to a successful run. You may wind up dying once or twice (If you suck) when playing on death incarnate, other than that death will not be a problem the main issue is the nonstop gauntlet. Believe me I would know how to play this game I'm in the Wolfenstein FaZe Clan, so just play for over 10,000 hours, catch all 802 pokemon, download windows 7, do 25 push ups and kill a nazi in real life. Then i may or may not pop it's a glitched achievement.