Eerie Ultimatum, Mitotic Slime, Phyrexian Altar, and Eternal Witness

Prerequisites

• Eerie Ultimatum in hand
• Mitotic Slime on the battlefield
• Phyrexian Altar on the battlefield
• Eternal Witness on the battlefield

Steps

1. Activate Phyrexian Altar twice by sacrificing Mitotic Slime and Eternal Witness, adding
2. When Mitotic Slime dies, it triggers, creating two 2/2 Ooze creature tokens
3. Activate Phyrexian Altar twice by sacrificing the Oozes, adding
4. When the Oozes die, they trigger, creating four 1/1 Ooze creature tokens
5. Activate Phyrexian Altar three times by sacrificing three Oozes, adding
6. Cast Eerie Ultimatum by paying , returning Eternal Witness and Mitotic Slime to the battlefield from your graveyard
7. When Eternal Witness enters the battlefield, it triggers, returning Eerie Ultimatum from your graveyard to your hand
8. Repeat

Results

• Infinite colored mana
• Infinite creature tokens
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite magecraft triggers
• Infinite sacrifice triggers
• Infinite storm count