Chainer, Dementia Master + K'rrik, Son of Yawgmoth + Gray Merchant of Asphodel + Ashnod's Altar

Prerequisites

• Your life total is 10 or greater.
• You have at least two opponents, or your devotion to black is at least ten.

Steps

1. 1Activate Ashnod's Altar by sacrificing Gray Merchant.
2. 2Activate Chainer by paying 9 life due to K'rrik, returning Gray Merchant from your graveyard to the battlefield as a Nightmare in addition to its other creature types.
3. 3When Gray Merchant enters, it triggers, causing each opponent to lose life equal to your devotion to black and causing you to gain that much life.
4. 4Repeat.

Effects

• Infinite colorless mana
• Infinite death triggers
• Infinite ETB
• Infinite lifegain
• Infinite lifegain triggers
• Infinite lifeloss
• Infinite LTB
• Infinite sacrifice triggers
• Return all creature cards from all graveyards to the battlefield under your control