Mortuary + Umbral Collar Zealot + Bolas's Citadel + Ornithopter

Mortuary

Umbral Collar Zealot

Bolas's Citadel

Ornithopter

How it works

1. Activate Umbral Collar Zealot by sacrificing Ornithopter
2. When Ornithopter dies, Mortuary triggers, putting Ornithopter from your graveyard onto the top of your library.
3. Resolve the Umbral Collar Zealot ability.
4. Cast Ornithopter from the top of your library by paying 0 life.
5. Repeat.

This loop turns free artifacts into an endless stream of triggers by leveraging Bolas's Citadel to cast cards directly from the top of your library for zero life. When you sacrifice Ornithopter to Umbral Collar Zealot, Mortuary catches it on its way to the graveyard and immediately places it right back onto the top of your library. From there, Umbral Collar Zealot's surveil ability helps smooth out your draws or fix your topdecks while the zero-cost flyer effortlessly loops in and out of play.