Got the legend achievement still no armour kinda annoying when this was an issue 3 years ago and it’s still not fixed
Try starting Halo 2’s Gravemind (other missions might work but I’m not sure) on legendary, leave it for a bit, you don’t even have to finish it, then quit campaign, saving data, and go on Halo 5. That should give you Helioskrill
Try to complete all the campaigns Solo on normal (the ones that you didn’t complete)… To update your data…