Mortuary + Sarcatog + Phyrexian Walker + Bolas's Citadel

Mortuary

Sarcatog

Phyrexian Walker

Bolas's Citadel

How it works

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

This clever loop turns zero-mana creatures into an engine of endless iteration by leveraging Mortuary to constantly recycle your fallen threats back to the top of your library. Bolas's Citadel is the true linchpin of the operation, allowing you to bypass mana costs entirely and cast that creature straight off the top for free by paying life instead. Meanwhile, Sarcatog acts as the reliable sacrifice outlet that sends the artifact creature to the graveyard in the first place, ensuring Phyrexian Walker can make its endless journey from battlefield to graveyard to library and back again.