Level 1 of DOOM Ultra-Nightmare Campaign. If you die on Ultra-Nightmare you have to start back at the beginning of the entire game, not just the level. You have to work on all the weapon upgrades as you're playing and you lose all progress for them if you die and you can't go back into levels to work on them or find missed secrets or Praetor tokens, of which you also lose all progress of if you die. You can't stop mid-level, but you can stop after a level is complete. You are able to fail or die in the rune trials because for many of them the game will put you in an unfair environment that you are not in before you start it. You have to win this long game in one life; when you die the file is erased.
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