Mortuary + Phyrexian Dreadnought + Gwenom, Remorseless + South Wind Avatar

Mortuary

Phyrexian Dreadnought

Gwenom, Remorseless

South Wind Avatar

How it works

1. Cast Phyrexian Dreadnought from the top of your library by paying 1 life.
2. When Phyrexian Dreadnought enters, it triggers, causing you to sacrifice it.
3. When Phyrexian Dreadnought dies, Mortuary and South Wind Avatar's first ability trigger.
4. Resolve the Mortuary trigger, putting Phyrexian Dreadnought from your graveyard onto the top of your library.
5. Resolve the South Wind Avatar trigger, causing you to gain 1 life.
6. South Wind Avatar's second ability triggers, causing each opponent to lose 1 life
7. Repeat.