Grenzo, Dungeon Warden, The Cauldron of Eternity, Phyrexian Altar, Dark Ritual, and Eternal Witness

Prerequisites

• Grenzo, Dungeon Warden on the battlefield
• The Cauldron of Eternity on the battlefield
• Phyrexian Altar on the battlefield
• Dark Ritual in hand
• Eternal Witness on the battlefield
• Grenzo has power 2 or greater
• available

Steps

1. Cast Dark Ritual by paying , adding
2. Activate Phyrexian Altar by sacrificing Eternal Witness, adding one mana of any color
3. When Eternal Witness dies, The Cauldron of Eternity triggers, putting Eternal Witness from your graveyard onto the bottom of your library
4. Activate Grenzo by paying , putting Eternal Witness from the bottom of your library into your graveyard, and then putting it onto the battlefield
5. When Eternal Witness 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

Results

• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite magecraft triggers
• Infinite sacrifice triggers
• Infinite storm count
• Put all creature cards with power less than or equal to Grenzo's from your library onto the battlefield