Otherworldly Escort + Amoeboid Changeling + Thornbite Staff + Bartolomé del Presidio

Otherworldly Escort

Amoeboid Changeling

Thornbite Staff

Bartolomé del Presidio

How it works

1. Activate Amoeboid Changeling's second ability by tapping it, causing Otherworldly Escort to lose all creature types until end of turn.
2. Activate Bartolomé del Presidio by sacrificing Otherworldly Escort.
3. When Otherworldly Escort dies, it and Amoeboid Changeling trigger.
4. Resolve the Amoeboid Changeling trigger, untapping it.
5. Resolve the Otherworldly Escort trigger, returning itself from your graveyard to the battlefield as a Spirit Detective.
6. Resolve the Bartolomé del Presidio ability.
7. Repeat.

This ingenious loop relies on a clever type-manipulation trick with Amoeboid Changeling to bypass Otherworldly Escort's built-in restriction against triggering when it dies while already a Spirit. By temporarily stripping away its creature types, Otherworldly Escort forgets its newfound Spirit status just in time to successfully trigger its own resurrection ability whenever you sacrifice it to Bartolomé del Presidio. Thornbite Staff can also join the machinery by granting untap triggers and extra pings, though the core sacrifice engine already endlessly pumps Bartolomé del Presidio full of counters and churns through your creatures' leaves-the-battlefield and death triggers.