Mortuary + Gray Merchant of Asphodel + Viscera Seer + Gwenom, Remorseless

Mortuary

Gray Merchant of Asphodel

Viscera Seer

Gwenom, Remorseless

How it works

1. Cast Gray Merchant either from your hand by paying 3 or from the top of your library by paying 5 life.
2. When Gray Merchant enters, it triggers, causing each opponent to lose life equal to your devotion to black and causing you to gain life equal to the life lost this way.
3. Activate Viscera Seer by sacrificing Gray Merchant.
4. When Gray Merchant dies, Mortuary triggers, putting Gray Merchant from your graveyard onto the top of your library.
5. Resolve the Viscera Seer ability.
6. Repeat.

This clever loop sets up an endless cycle of sacrifice and rebirth by leveraging Viscera Seer to feed Gray Merchant of Asphodel directly back into the graveyard. Thanks to Mortuary, every time the Merchant hits the graveyard, it effortlessly slides right back onto the top of your library instead of staying put. From there, Gwenom, Remorseless lets you bypass traditional mana costs entirely by casting the Merchant straight from the top of your library for a mere 5 life, which is easily offset by the massive life drain and lifegain triggered by the Merchant's own entry ability.