Tombstone Stairwell, and Poison-Tip Archer

Prerequisites

• Tombstone Stairwell on the battlefield
• Poison-Tip Archer on the battlefield

Steps

1. At the beginning of each upkeep, Tombostone Stairwell's first ability triggers, causing each player to create a 2/2 Zombie creature token for each creature card in their graveyard
2. At the beginning of each end step, Tombstone Stairwell's second ability triggers, destroying all tokens created by it
3. When the token(s) die, Poison-Tip Archer triggers that many times, causing each opponent to lose that much life
4. Repeat during each turn

Results

• Near-infinite lifeloss
• Near-infinite ETB
• Near-infinite LTB
• Near-infinite death triggers