Mortuary + Carrion Feeder + Gwenom, Remorseless + Sifa Grent

Mortuary

Carrion Feeder

Gwenom, Remorseless

Sifa Grent

How it works

1. Cast Carrion Feeder by paying its mana cost.
2. Activate Carrion Feeder by sacrificing it.
3. When Carrion Feeder dies, Mortuary and Sifa Grent trigger.
4. Resolve the Mortuary trigger, putting Carrion Feeder from your graveyard onto the top of your library.
5. Resolve the Sifa Grent trigger, causing target opponent to lose 1 life and you to gain 1 life.
6. Cast Carrion Feeder from the top of your library by paying 1 life.
7. Repeat from step 2.