Olivia, Mobilized for War + Umbral Collar Zealot + Grim Haruspex

Olivia, Mobilized for War

Umbral Collar Zealot

Grim Haruspex

How it works

1. Activate Umbral Collar Zealot by sacrificing the persist creature.
2. When the persist creature dies, it and Grim Haruspex trigger.
3. Resolve the Grim Haruspex trigger, causing you to draw a card.
4. Resolve the persist creature's trigger, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
5. When the persist creature enters the battlefield, Olivia triggers, putting a +1/+1 counter on the persist creature and causing you to discard a card.
6. Resolve the Umbral Collar Zealot ability.
7. Repeat.

This clever engine uses a persist creature as an endless sacrifice fodder, which gets immediately recycled back to the battlefield to fuel Umbral Collar Zealot's activation cost. As that creature enters anew, Olivia, Mobilized for War steps in with her passive-triggered ability to hand out a +1/+1 counter and force a discard, neutralizing the creature's -1/-1 counter so the loop can keep going. Meanwhile, Grim Haruspex quietly watches the carnage from the sidelines, cashing in each death to keep your hand full while Umbral Collar Zealot trims away unwanted top-decks with surveil.