Mikaeus, the Unhallowed + Altar of Dementia + Restless Apparition

Mikaeus, the Unhallowed

Altar of Dementia

Restless Apparition

How it works

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