Opponent played shifting scroll early in the game which was the mage secret Ice Block. Delivered lethal damage and the secret triggered. Then played Netherspire Historian before the animation of the secret and the scroll finished. Historian never triggered the discover despite dragons in hand and the shifting scroll remained on screen. Turn lapsed due to rope and opponents turn was then infinite, unable to play cards.
Chameleos or Shifting Scroll creating secrets that cause a game freeze has been reported multiple times and Blizzard is aware.
Try a force restart immediately.
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