Mortuary + Altar of Dementia + Phyrexian Walker + Bolas's Citadel

Mortuary

Altar of Dementia

Phyrexian Walker

Bolas's Citadel

How it works

1. Activate Altar of Dementia 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 Altar of Dementia ability.
4. Cast Phyrexian Walker from the top of your library by paying 0 life.
5. Repeat.

This clever loop uses Bolas's Citadel to cast creatures directly from the top of your library for zero life, completely bypassing traditional mana costs. Once Phyrexian Walker is on the battlefield, you sacrifice it to Altar of Dementia to mill an opponent, triggering Mortuary to seamlessly place the artifact creature right back on top of your library. Because Phyrexian Walker has a mana value of zero, Bolas's Citadel lets you replay it indefinitely without losing any life, creating an unstoppable self-sustaining engine of infinite sacrifices, deaths, and library milling.