Phyrexian Altar, Tariel, Reckoner of Souls, and Thornbite Staff

Prerequisites

• Phyrexian Altar on the battlefield
• Tariel, Reckoner of Souls on the battlefield
• Thornbite Staff on the battlefield
• Thornbite Staff attached to Tariel
• Tariel does not have summoning sickness
• At least one opponent has at least one creature in their graveyard

Steps

1. Activate Tariel to return a random creature from target opponent's graveyard to the battlefield
2. Sacrifice the returned creature to Phyrexian Altar, triggering Thornbite Staff and untapping Tariel
3. Repeat steps 1-2

Results

• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers