Mortuary + Phyrexian Altar + Bontu's Monument + Gwenom, Remorseless

Mortuary

Phyrexian Altar

Bontu's Monument

Gwenom, Remorseless

How it works

1. Activate Phyrexian Altar by sacrificing a creature with mana value 1 or less.
2. When the creature dies, Mortuary triggers, putting the creature from your graveyard onto the top of your library.
3. Cast the creature from the top of your library by paying 1 life.
4. Bontu's Monument triggers, causing you to gain 1 life and each opponent to lose 1 life.
5. Repeat.

This cunning loop transforms the life-paying ability of Gwenom, Remorseless into a self-sustaining engine by letting you repeatedly cast a cheap creature off the top of your library. Mortuary ensures that whenever you sacrifice that creature to Phyrexian Altar for mana, it goes right back onto the top of your library instead of staying in the graveyard. Meanwhile, Bontu's Monument quietly removes the mana cost of your black creature spells while turning every single loop iteration into a lethal drain on your opponents, offsetting the life you paid to Gwenom.