'United in Stormwind' Mystery won't trigger

[CMac-1595]

all of the “mystery” quests involving decks or specific HS cards are bugged, currently.

there are few threads on it. Hopefully Blizzard sees and fixes soon!

There may be a wonky solution by using other variants of the same card, per this post/thread below, but I’m not sure it’s been tested yet:

Unable to begin Mystery in the Barrens - Hunter Challenge

I suspect the challenge isn’t working for a lot of factors actually. Looking at the requirements to start the challenge vs the changes to the coreset, it is likely the challenge required: Core Murloc Tinyfin Core Acidic Swamp Ooze Core Mossy Horror Core Krag’wa, the Frog All of which left the Core set with rotation. So check all of them to see if they are instead pulling in the non-core versions from your various wild sets like Rastakhan and Witchwood.