Cast Atzocan Archer by paying {2}{G}.
Atzocan Archer enters the battlefield, fighting Dread Slaver.
Atzocan Archer dies, triggering Dread Slaver, returning Atzocan Archer to the battlefield as a black Zombie in addition to its other types.
Repeat from step 2.

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Atzocan Archer

Dread Slaver

Vampirism

Cause the additional creature to die.
Sanguinary Priest triggers, dealing 1 damage to you and causing you to gain one life.
Darien triggers, creating a 1/1 Soldier creature token.
The Soldier enters the battlefield as a 0/0 due to Vampirism and dies as a state-based action due to having zero toughness.
Repeat from step 2.

Infinite lifegain triggers

Darien, King of Kjeldor

Sanguinary Priest

Activate Ruthless Ripper's morph ability by revealing a black card from your hand, turning it face-up and triggering its ability.
Ruthless Ripper dies as a state-based action due to having zero or less toughness.
Yedora triggers, returning Ruthless Ripper to the battlefield face-down as a Forest land.
Resolve the Ruthless Ripper trigger from step 1, causing target player to lose 2 life.
Repeat.

Combos with "Vampirism"