Gravespawn Sovereign, Cursecatcher, and Intruder Alarm

Prerequisites

• Gravespawn Sovereign on the battlefield
• Cursecatcher on the battlefield
• Intruder Alarm on the battlefield
• At least four other Zombies on the battlefield

Steps

1. Whenever an opponent casts an instant or Sorcery, sacrifice Cursecatcher to counter that spell unless that opponent pays
2. Tap 5 untapped zombies you control to return Cursecatcher to the battlefield
3. Intruder Alarm triggers, untapping all creatures
4. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Lock on opponent's instants and sorceries