Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Mikaeus, the Unhallowed + Yahenni, Undying Partisan

Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight

Mikaeus, the Unhallowed

Yahenni, Undying Partisan

How it works

1. Activate Yahenni by sacrificing another nontoken non-Human creature
2. When the creature dies, its undying ability triggers, returning the creature from your graveyard to the battlefield with a +1/+1 counter on it.
3. Activate Yahenni by sacrificing the creature with a +1/+1 counter on it.
4. When the creature dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
5. Resolve the Yahenni abilities from step 1 and 3.
6. Repeat.

This clever loop relies on the brilliant intersection of two different resurrection mechanics granted to your team. With Mikaeus, the Unhallowed in play, your non-Human creatures are blessed with undying, allowing them to return with a +1/+1 counter the first time they perish. However, once Eirdu, Carrier of Dawn transforms into its Isilu, Carrier of Twilight face, those very same nontoken creatures also gain persist. By feeding a creature to Yahenni, Undying Partisan, you trigger its undying ability, but when that same creature dies a second time with its new +1/+1 counter, the persist ability takes over to bring it back with a -1/-1 counter instead. Because +1/+1 and -1/+1 counters neatly annihilate each other upon entering the graveyard, this back-and-forth cycle can be repeated indefinitely to generate boundless sacrifice, entry, and death triggers.