Recently was playing in the Dalaran Heist adventure mode and came across a bug when playing against Draemus. I had played a Flame Elemental card, which spawned from the Flame Geyser card. The AI had a mage secret in play, and when my Flame Elemental entered the battlefield, it popped the secret and showed Chameleos on my screen, but never showed the Potion of Polymorph card taking effect in the left side card log. Then the game froze up and would not let me end turn or concede.
Chameleous and secret freeze has been reported multiple times and Blizzard is aware:
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