Most recent game in logs:
On my end step, opponent tapped Twitching Doll to float mana and add a counter. I was granted no opportunity to react to this despite having 4 untapped lands, including a Plains, as well as Seized From Slumber in hand. I should have been able to cast a reduced cost Seized From Slumber to destroy the tapped Twitching Doll. On opponent's following turn they activated the Twitching Doll's ability, saccing it and creating spider tokens, this bug created a game deciding shift and led to my loss and elimination from the event.