Grenzo, Dungeon Warden + The Cauldron of Eternity + Phyrexian Altar + Dark Ritual + Vampire Charmseeker

Grenzo, Dungeon Warden

The Cauldron of Eternity

Phyrexian Altar

Dark Ritual

Vampire Charmseeker

How it works

1. Cast Dark Ritual by paying , adding .
2. Activate Phyrexian Altar by sacrificing Vampire Charmseeker, adding one mana of any color.
3. When Vampire Charmseeker dies, The Cauldron of Eternity triggers, putting Vampire Charmseeker from your graveyard onto the bottom of your library.
4. Activate Grenzo by paying 2, putting Vampire Charmseeker from the bottom of your library into your graveyard, and then putting it onto the battlefield.
5. When Vampire Charmseeker enters the battlefield, it triggers, returning Dark Ritual from your graveyard to your hand.
6. Repeat.
7. Once you have infinite mana, you may activate Grenzo's ability any number of times.

This intricate loop relies on looping Vampire Charmseeker back and forth to continuously recycle spells and fuel your board. With The Cauldron of Eternity actively tucking every dying creature to the bottom of your library, Grenzo, Dungeon Warden can easily cheat Vampire Charmseeker right back onto the battlefield for just two mana. As Vampire Charmseeker enters the battlefield, its triggered ability plucks Dark Ritual out of your graveyard and returns it to your hand, providing the black mana needed to recast it. Meanwhile, sacrificing Vampire Charmseeker to Phyrexian Altar generates the colored mana required to keep Grenzo's ability firing, creating an unstoppable engine that yields infinite mana, sacrifices, and enters-the-battlefield triggers.