Mikaeus, the Unhallowed + Umbral Collar Zealot + Lesser Masticore

Mikaeus, the Unhallowed

Umbral Collar Zealot

Lesser Masticore

How it works

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