Impostor Syndrome + Combat Celebrant + Rising of the Day

Impostor Syndrome

Combat Celebrant

Rising of the Day

How it works

1. Declare Combat Celebrant as an attacker, choosing to exert it as it attacks and triggering its ability, causing you to untap all other creatures you control and to get an additional combat phase after this one.
2. Deal combat damage to an opponent using Combat Celebrant, triggering Impostor Syndrome, creating a token copy of Combat Celebrant that isn't legendary.
3. During your next combat phase, declare Combat Celebrant and the Combat Celebrant token as attackers, choosing to exert the Combat Celebrant token as it attacks.
4. The Combat Celebrant token triggers, causing you to untap all other creatures you control and to get an additional combat phase after this one.
5. Repeat from step 2.

This brilliant sequence centers on the synergy between Combat Celebrant and Impostor Syndrome, where dealing combat damage with the Celebrant lets the Impostor create a nonlegendary copy of it. While the steps walk through looping these exertion triggers for infinite combat phases, Rising of the Day quietly does crucial heavy lifting behind the scenes by giving your new token copy haste so it can immediately join the attack. Because the copy isn't legendary, you bypass the legend rule and can safely retain multiple copies while continuously generating fresh untap and combat steps.