I’m trying to get the Helioskrill armour in Halo 5, and I have completed the campaign on MCC on legendary before, but I’ve realised that some missions didn’t register (no achievement for them).
I thought I would go back and complete the ones that I didn’t get the achievements for. First one I did, The Arbiter completed properly, but I have done The Oracle three times now, and the achievement still hasn’t come up!
What can I do?