Mikaeus, the Unhallowed + Viscera Seer + Obstinate Gargoyle

Mikaeus, the Unhallowed

Viscera Seer

Obstinate Gargoyle

How it works

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