Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Umbral Collar Zealot + Gleeful Arsonist

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

Umbral Collar Zealot

Gleeful Arsonist

How it works

1. Activate Umbral Collar Zealot by sacrificing Gleeful Arsonist
2. When Gleeful Arsonist dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
3. Activate Umbral Collar Zealot by sacrificing Gleeful Arsonist
4. When Gleeful Arsonist dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
5. Resolve both Umbral Collar Zealot abilities from step 1 and 3.
6. Repeat.