Mortuary + Blood Pet + Susurian Voidborn + Gwenom, Remorseless

Mortuary

Blood Pet

Susurian Voidborn

Gwenom, Remorseless

How it works

1. Activate Blood Pet by sacrificing it.
2. When Blood Pet dies, Mortuary and Susurian Voidborn trigger.
3. Resolve the Mortuary trigger, putting Blood Pet from your graveyard onto the top of your library.
4. Resolve the Susurian Voidborn trigger, causing you to gain 1 life and target opponent to lose 1 life.
5. Cast Blood Pet from the top of your library by paying 1 life.
6. Repeat.

This delightfully twisted loop turns the humble Blood Pet into an engine for infinite carnage by exploiting the library-stacking power of Mortuary whenever a creature heads to the graveyard. While the Pet's sacrifice initially fuels your mana pool, the background drain from Susurian Voidborn ensures your opponents bleed out with every single iteration. Finally, Gwenom, Remorseless ties the whole room together by letting you bypass conventional costs, allowing you to replay the sacrificed creature straight from the top of your library for a tiny sliver of life instead of mana.