Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Umbral Collar Zealot + Ambitious Aetherborn

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

Umbral Collar Zealot

Ambitious Aetherborn

How it works

1. Activate Umbral Collar Zealot by sacrificing Ambitious Aetherborn.
2. When Ambitious Aetherborn dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When Ambitious Aetherborn enters, its fabricate ability triggers, putting a +1/+1 counter on it.
4. Resolve the Umbral Collar Zealot ability.
5. Repeat.

This looping engine centers on the dual-faced Eirdu, Carrier of Dawn and Isilu, Carrier of Twilight, whose back face grants persist to your other nontoken creatures. When you sacrifice Ambitious Aetherborn to Umbral Collar Zealot, the persist trigger brings the Aetherborn right back to the battlefield. Because Ambitious Aetherborn also features fabricate 1, its entry triggers allow you to place a +1/+1 counter that immediately cancels out the incoming -1/-1 counter from persist. This resetting mechanism lets you endlessly repeat the sacrifice loop to fuel infinite surveil, death triggers, and leaves-the-battlefield counts.