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I was playing against an AI and managed to get the mana needed for the Bearer of Silence's cast trigger to make the opponent sacrifice a creature, i cast the eldrazi, was prompted asking if i wanted to pay one waste and one generic, and i clicked yes, and then when i tried to pay mana, i was prompted with a pop up error suggesting that i cannot play the spell and that if i wanted to use it's effect i would have to recast the spell, this happens every cast, and unfortunately once i pay the mana for the creature before it's trigger, i can't take it back after that, so i get excited hoping for removal of sorts, and then it's gone, i'm stuck with a flier that can't block and so on, i am not really that upset, i just hope it gets patched is all