Mikaeus, the Unhallowed + Carrion Feeder + Obstinate Gargoyle

Mikaeus, the Unhallowed

Carrion Feeder

Obstinate Gargoyle

How it works

1. Activate Carrion Feeder 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 Carrion Feeder ability.
4. Activate Carrion Feeder 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 Carrion Feeder ability.
7. Repeat.