Mortuary + Gray Merchant of Asphodel + Ashnod's Altar + Gwenom, Remorseless

Mortuary

Gray Merchant of Asphodel

Ashnod's Altar

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 Ashnod's Altar by sacrificing Gray Merchant.
4. When Gray Merchant dies, Mortuary triggers, putting Gray Merchant from your graveyard onto the top of your library.
5. Repeat.

This clever loop turns Ashnod's Altar into an engine that recycles Gray Merchant of Asphodel endlessly, draining your opponents and padding your life total with every iteration. The key to keeping the chain unbroken is Mortuary, which intercepts Gray Merchant as it dies and neatly tucks it right back onto the top of your library. While you can manually cast the Merchant for its standard mana cost to kick things off, Gwenom, Remorseless provides an incredible alternate axis: once it attacks, its passive ability lets you peer at the top of your library and cast Gray Merchant straight from the top, converting your life total into the mana value needed to recast it.