Mikaeus, the Unhallowed + Bloodied Ghost + Woe Strider

Mikaeus, the Unhallowed

Bloodied Ghost

Woe Strider

How it works

1. Activate Woe Strider 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 Woe Strider ability.
4. Repeat.