Mortuary + Ashnod's Altar + Phyrexian Walker + Bolas's Citadel

Mortuary

Ashnod's Altar

Phyrexian Walker

Bolas's Citadel

How it works

1. Activate Ashnod's Altar by sacrificing Phyrexian Walker
2. When Phyrexian Walker dies, Mortuary triggers, putting Phyrexian Walker from your graveyard onto the top of your library.
3. Cast Phyrexian Walker from the top of your library by paying 0 life.
4. Repeat.

This clever loop turns the zero-cost artifact creature Phyrexian Walker into an engine for infinite mana and death triggers, all while neatly bypassing traditional resource constraints. Ashnod's Altar provides the sacrifice outlet to generate two colorless mana while sending the Walker to the graveyard, where Mortuary immediately intercepts it to place the card right back on top of your library. With Bolas's Citadel granting you the ability to play spells directly from the top of your library by paying life instead of mana, you can recast the Phyrexian Walker for zero life and repeat the entire cycle endlessly.