So far in playing H:CEA i have unlocked 3 achievements after completing the first level. Naughty Naughty H3:ODST: Kill 10 Engineers Arrival Activate the first terminal and Truth and Reconciliation Complete the third level. anyone else have this happen?
“Ready when it’s ready.”
Yeah I’ve unlocked loads of totally unrelated achievements on Steam version. Apparently I’ve beaten missions 3 and 4 but I’ve only beaten 1 and 2.
I’m now not unlocking any achievements 
done
When I finished downloading the CE and firing up the game I received an Achievement for HALO3 ODST (Naughty Naughty)
also when I finished the Pillar of Autumn I received the Truth and Reconciliation achievement lol.
The Achievement system is drunk tbh (or People behind it)
The achievment for naughty naughty for killing engineers were buggy before and got unlocked after the patch, because you were able to kill those types in reach
e.g in new alexandria .
As for me the achievment were right as I did pillar of autumn and halo also for par score and par time
The only issue were that the icons for the missions are mixed up
PoA was III
And halo was IV which obv is a mistake
It also seems, at least for me, that only the Steam achievements are mixed up. finishing missions 1 and 2 unlocked the steam achievements for 3 and 4 respectively including the achievement for par time but the Xbox companion thing unlocked the correct achievements. However both are unlocking the correct terminal achievements…
I’ve had the same issue. Pillar of Autumn and Halo missions unlock Mission 3 and 4 achievements respectively on Steam version. Skull and Terminal Achievements are correct though, as are the par score and time ones.
Unrelated, but there’s an issue with Elites on Halo One Shot Killing when you’re on full health and shields too at the third escape pod site you go to (last one in the mission). Elites elsewhere in the level didn’t have this problem, seems rather odd.