Amy is playing against Nigel in a Modern PPTQ, with her Eldrazi deck. She controls an Eldrazi Monument, an Eldrazi Displacer, and an Eldrazi Skyspawner, and several lands. Amy untaps, draws, then attacks with all of her creatures. While thinking about blockers, Nigel notices that Eldrazi Monument should have triggered and calls for a judge. Amy admits to missing her trigger, but also asks if she can use her Displacer to blink her Skyspawner to make a token to sacrifice. What do you do to fix the situation, and can Amy do what she wants?
Amy receives a warning for Missed Trigger since Eldrazi Monument trigger is detrimental. The trigger may look like it has a default action, but since it says “if you can’t” instead of “if you don’t”, the trigger will go on the stack instead of being resolved immediately. Ask Nigel if he wants the trigger to go on the stack, and if he does, Amy can respond to the trigger. In regards to Amy’s question, the IPG says “No player may make choices involving objects that would not have been legal choices when the ability should have triggered.” This means that the additional new token will not be a legal choice, and since Eldrazi Skyspawner becomes a new object when it changes zones, it won’t be a legal choice either.
Judges feel free to answer on Judge Apps!