Mikaeus, the Unhallowed + Otherworldly Escort + Altar of Dementia

Mikaeus, the Unhallowed

Otherworldly Escort

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Otherworldly Escort.
2. When Otherworldly Escort dies, it triggers, returning itself from your graveyard to the battlefield as a Spirit Detective.
3. Resolve the Altar of Dementia ability.
4. Activate Altar of Dementia by sacrificing Otherworldly Escort.
5. When Otherworldly Escort 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.