I beat HALO CE on legendary BUT the achievement says im at 30% completion, same with halo waypoint. I showed on my Twitter GK_FROM_YOUTUBE proof that I completed HALO CE on legendary. Pls fix this, I went through A LOT OF STRESS beating it on legendary.
You might want to report this bug here.
Other than that, I don’t know any other methods besides replaying the missions to unlock the achievement. Make sure your internet doesn’t drop during sessions just to be safe.
Replaying the 70% (7 missions)
is out of the question so im gonna go with option 1.
You should try a hard reset on xbox, it usually works.
Ill try thx
It didnt work. But thx for helping.
No problem! ohh… some achievements may take some time to unlock, so just be patient 
If nothing happens, you should follow Illusive blue suggestion.
If you play with the Bandanna Skull and Grunt Funeral Skull on, keep your distance, and be cautious, you can complete the levels on Legendary with very little hassle. The only levels that would give you trouble is Two Betrayals and The Maw.
Did you play the missions offline? Achievement progress is only tracked online.
I Remember a bug like that from the famous achievement warlord… In that case it unlocked me randomly… Maybe it’s like that… Or try the hard reset as the others said.
MCC sometimes doesn’t record your completion for a level. I think your only option is to replay those levels. You can try blasting through on Easy to maybe force the game to “push” your Legendary times through, but that may not work. You need to be connected to Live for your times to upload to Waypoint.
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> MCC sometimes doesn’t record your completion for a level. I think your only option is to replay those levels. You can try blasting through on Easy to maybe force the game to “push” your Legendary times through, but that may not work. You need to be connected to Live for your times to upload to Waypoint.
Oh yeah, there was a bug that affected the tracking of mission progress.
> 2535438791766010;1:
> I beat HALO CE on legendary BUT the achievement says im at 30% completion, same with halo waypoint. I showed on my Twitter GK_FROM_YOUTUBE proof that I completed HALO CE on legendary. Pls fix this, I went through A LOT OF STRESS beating it on legendary.
How long ago did you complete each mission? You may have completed some missions before they fixed the bug.
I played all levels online, I beat the game last night so the bug was already fixed, and I already tried hard reset. The achievement popping up randomly could happen but im not sure. Im gonna go to the forum where people can get their achievement glitches fixed so ill go there. Thx for trying to help guys!
> 2535438791766010;13:
> I played all levels online, I beat the game last night so the bug was already fixed, and I already tried hard reset. The achievement popping up randomly could happen but im not sure. Im gonna go to the forum where people can get their achievement glitches fixed so ill go there. Thx for trying to help guys!
I will keep searching for answers and let you know if I discover anything. I’m sorry I haven’t been able to help you.
> 2533274859620752;14:
> > 2535438791766010;13:
> > I played all levels online, I beat the game last night so the bug was already fixed, and I already tried hard reset. The achievement popping up randomly could happen but im not sure. Im gonna go to the forum where people can get their achievement glitches fixed so ill go there. Thx for trying to help guys!
>
> I will keep searching for answers and let you know if I discover anything. I’m sorry I haven’t been able to help you.
You have helped as much as you could and thank for that. Ill tell you when it gets fixed. Thank you guys for trying to help.
> 2535438791766010;15:
> > 2533274859620752;14:
> > > 2535438791766010;13:
> > > I played all levels online, I beat the game last night so the bug was already fixed, and I already tried hard reset. The achievement popping up randomly could happen but im not sure. Im gonna go to the forum where people can get their achievement glitches fixed so ill go there. Thx for trying to help guys!
> >
> > I will keep searching for answers and let you know if I discover anything. I’m sorry I haven’t been able to help you.
>
> You have helped as much as you could and thank for that. Ill tell you when it gets fixed. Thank you guys for trying to help.
Of course! Let us know how things go.
Silly question - but what does your in-game menus say?
Does it show you’ve completed 10/10 on legendary?
[edit]
nevermind - i re-read your first post and found your twitter post showing completion.