Guan Yu, Sainted Warrior + Remembrance + Deathrender + Altar of Dementia

Guan Yu, Sainted Warrior

Remembrance

Deathrender

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Guan Yu.
2. When Guan Yu dies, it, Deathrender and Remembrance trigger.
3. Resolve the Guan Yu trigger, causing you to shuffle it into your library from your graveyard.
4. Resolve the Remembrance trigger, causing you to search your library for Guan Yu and put it into your hand.
5. Resolve the Deathrender trigger, putting Guan Yu from your hand onto the battlefield, and attaching Deathrender to it.
6. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Guan Yu's power.
7. Repeat.

This clever loop turns Guan Yu, Sainted Warrior into a self-sustaining engine of relentless mill. By sacrificing him to Altar of Dementia, you trigger a clever stack interaction where Guan Yu's own replacement-style graveyard shuffle trigger fights with Remembrance; you let the shuffle resolve first, and then Remembrance efficiently finds that exact same Guan Yu and pulls him right back to your hand. Meanwhile, Deathrender watches the equipped Guan Yu bite the dust and immediately cheats him back onto the battlefield, automatically re-equipping itself to pump his power for the next sacrifice.