Mikaeus, the Unhallowed + Otherworldly Escort + Thermopod

Mikaeus, the Unhallowed

Otherworldly Escort

Thermopod

How it works

1. Activate Thermopod 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 Thermopod ability.
4. Activate Thermopod 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 Thermopod ability.
7. Repeat.