Mikaeus, the Unhallowed + Morselhoarder + Umbral Collar Zealot

Mikaeus, the Unhallowed

Morselhoarder

Umbral Collar Zealot

How it works

1. Activate Umbral Collar Zealot by sacrificing Morselhoarder.
2. When Morselhoarder dies, its undying ability triggers, returning it from your graveyard to the battlefield without a +1/+1 counter on it due to its replacement effect.
3. Resolve the Umbral Collar Zealot ability
4. Repeat.

This elegant loop harnesses Mikaeus, the Unhallowed to grant undying to Morselhoarder, ensuring that whenever the Elemental Ouphe hits the graveyard, it returns to the battlefield with a +1/+1 counter. Because those counters instantly annihilate the two -1/-1 counters Morselhoarder naturally enters with through state-based actions, its death-and-return cycle resets its counter tally completely cleanly. While this churns infinitely, Umbral Collar Zealot provides the necessary outlet to sacrifice Morselhoarder repeatedly, fueling the loop while letting you surveil through your entire deck to dig for whatever finishing piece you need.