Heroic Episode Glitched

Games Other Halo
1

I’ve played all of Artifact through on Heroic twice now; the challenge still didn’t pop. On XBOX it shows up as “Artifact”, on the website it shows as the troubling “Id -1 is invalid”.

What’s the deal?

> Heroic Episode
> Type: Spartan Ops
> Complete all missions in Chapter Id -1 is invalid. on Heroic or higher difficulty.

2

Same here but I only played through them online. Maybe they want you to do it solo? I have beaten them at least 4 times or so.