Tombstone Stairwell, and Vein Ripper

Prerequisites

• Tombstone Stairwell on the battlefield
• Vein Ripper 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, Vein Ripper triggers that many times, causing an opponent to lose twice that much life and you to gain twice that much life
4. Repeat during each turn

Results

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