Not usable in Arena, specifically in RSS, haven’t tried premade arena.
Despite also saying in the tooltip that it’s usable in all rated environments.
Doesn’t work in Solo Shuffle, BG Blitz, Arena Skirms. Seems like it only works in not rated content minus the arena not being usable. Idk why more haven’t reported this.
After this post, I was talking with a friend who had been using them, apparently it had been working in rated, but then was disabled.
I assume the Blizzard devs have a flag on items to enable them in rated environments, but there was wacky math going on for a mode, so they flagged the item to disable it, so they could fix it.
I guess that is easier than disabling it for specific modes.