Mikaeus, the Unhallowed, Cauldron of Souls, Intruder Alarm, Animate Artifact, and Viscera Seer

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Cauldron of Souls on the battlefield
• Intruder Alarm on the battlefield
• Animate Artifact on the battlefield
• Viscera Seer on the battlefield
• Animate Artifact attached to Cauldron of Souls
• Cauldron of Souls does not have summoning sickness

Steps

1. Activate Viscera Seer by sacrificing itself
2. When Viscera Seer dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
3. When Viscera Seer enters the battlefield, Intruder Alarm triggers, untapping all creatures
4. Resolve the Viscera Seer ability, causing you to scry 1
5. Activate Cauldron of Souls by tapping it, giving the creature persist until end of turn
6. Activate Viscera Seer by sacrificing itself
7. When Viscera Seer dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
8. When Viscera Seer enters the battlefield, Intruder Alarm triggers, untapping all creatures
9. Resolve the Viscera Seer ability, causing you to scry 1
10. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite scry 1
• Infinite untap of all creatures