When playing Caldera Breaker on at least Android, (I assume this also happens on iOS) Caldera breaker exiles all of the mountains in your deck until it dies, upon which those mountains are put on the battlefield. However, when given the option to sacrifice Caldera Breaker, (I tried to use Corrupted Conviction specifically) the game would not let me select Caldera Breaker and would just open or close a list of all the cards exiled by Caldera Breaker. I can't interact with the card period which also means I can't block with it to kill it either. The card gets turned into a mill yourself of all of your remaining red sources for six mana and try to figure out how to win from here.