Collectible Card Game Headquarters

Describe the Bug:
I cast 3,4 times Pieces of the Puzzle and each time game went on thinking for ever.

Which card did behave improperly ?
Pieces of the Puzzle

Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
Manalink 2016/08/07: Eldritch Moon, duel

What exactly should be the correct behavior/interaction ?
Pieces of the Puzzle

Are any other cards possibly affected by this bug ?
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It's because the choice is mandatory. (And it's really frightening that the tutoring functions just loop forever for a mandatory choice when there's no valid card to pick.) Fixed that in 2b3449f.

Also doesn't reveal the cards.