Mortuary + Umbral Collar Zealot + Crimson Kobolds + Gwenom, Remorseless

Mortuary

Umbral Collar Zealot

Crimson Kobolds

Gwenom, Remorseless

How it works

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

This clever loop turns zero-mana cardboard into an engine of endless triggers by relying on Gwenom, Remorseless to peer into the future and bypass mana costs with life payments. When you sacrifice Crimson Kobolds to Umbral Collar Zealot, Mortuary instantly catches it on the way to the graveyard and stacks it right back on top of your library. From there, Gwenom, Remorseless lets you cast the kobolds straight off the library for zero life, feeding the zealot's sacrifice altar all over again.