Mikaeus, the Unhallowed + Bloodied Ghost + Carrion Feeder

Mikaeus, the Unhallowed

Bloodied Ghost

Carrion Feeder

How it works

1. Activate Carrion Feeder by sacrifiicing Bloodied Ghost.
2. When Bloodied Ghost dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it. When it enters, Bloodied Ghost will put a -1/-1 counter on itself, removing the +1/+1 counter.
3. Resolve the Carrion Feeder ability.
4. Repeat.