Mikaeus, the Unhallowed + Bloodflow Connoisseur + Rendclaw Trow

Mikaeus, the Unhallowed

Bloodflow Connoisseur

Rendclaw Trow

How it works

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