You’re watching the last match of round 3 of a Dragons of Tarkir/Fate Reforged Limited PPTQ. Anna controls Champion of Arashin and Anafenza, Kin-Tree Spirit, while Nalick controls no creatures. On her turn, Anna casts Arashin Foremost, points at her Champion of Arashin and says, “Both triggers on champion,” then attacks with the Champion of Arashin and Anafenza. Nalick looks at his hand for a few seconds before saying, “No Blocks.” Anna says, “Ok, so you take eight… no wait, ten! I didn’t put the bolster counter on champion!” Nalick looks at you and says, “Judge, how does that work?”

What do you do?

Judges, feel free to discuss this scenario on Judge Apps!

[expand title=Answer]Thank you all for your thoughtful discourse, let’s wrap this one up! This scenario appears at first to be a perfect fit for the newest change to trigger policy, which says that if a trigger causes a visible change to the board or requires a choice on resolution, that action or choice must be made before changing steps or casting something at sorcery speed, in order for the trigger not to have been missed. However, there’s a very important detail to note about the bolster trigger: As it resolves, it requires a choice between creatures you control with the least toughness.

By indicating her choice of Champion of Arashin before attacking, Anna satisfied the conditions for acknowledging the trigger. However, she unfortunately did not finish resolving the trigger by placing the counter on to her creature. As such, she committed a Game Rule Violation and will receive a warning. Nalick, by not preventing this error, also has some responsibility for the error and as such receives a warning for Failure to Maintain the Game State. As relatively little time has passed since the error, and no partial fixes are applicable to this situation, we will rewind the situation to the point of the mistake. Anna’s attacking creatures will be untapped, and the game resumes during her main phase when the bolster trigger is resolving.
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