I just spent over an hour going through library on heroic (and I made sure multiple times that it was heroic), and I never died. The achievement that just happened never popped up for me. That is the only achievement I don’t have in the entire Halo series, and it wouldn’t even work for me. Is the achievement glitched?
If you did it with someone else on the same xbox and they died then that’s why.
> If you did it with someone else on the same xbox and they died then that’s why.
That kind of makes me mad that my second player only died once at the beginning because I did a grenade jump wrong. Even so, I think that is a glitch even if it doesn’t unlock for that.
i had the same issues attempting it in co-op.
do it solo and speed run it, make sure u don’t revert either. only takes 10 minutes
There is a trick on single player you can use to revert check point RIGHT b4 you die. You need to be able to predict a foresight of your death by watching your health. This does not work over live COOP because the game cannot be paused. I advise single player. Its like the LASO challenges on single player were you can cheat the system.
Will work if:
You don’t die. Revert check point if as your shields are being depleted if you cannot engage and control the situation.
Monitor you health 24 7
Be patient this isn’t the speed run challenge!
Single player-----> no lag issues!
try it out and remember if you die u have to start over, the game can recongize a death compared to low shields and health out come!
> i had the same issues attempting it in co-op.
>
> do it solo and speed run it, make sure u don’t revert either. only takes 10 minutes
You can revert if you don’t die in single player!
Try this guide if you wanna do it again 
I did it by myself last night, and it was actually easy for me with the bandanna skull on. I was about to die once, and I saved and quit. Then I resumed the game, and I still got the achievement after I finished it.