Infernal Vessel, Luminous Broodmoth, and Grimgrin, Corpse-Born

Prerequisites

• Infernal Vessel on the battlefield
• Luminous Broodmoth on the battlefield
• Grimgrin, Corpse-Born on the battlefield

Steps

1. Activate Grimgrin by sacrificing Infernal Vessel
2. When Infernal Vessel dies, it triggers, returning itself from your graveyard to the battlefield as a Demon in addition to its other types
3. Resolve the Grimgrin ability
4. Activate Grimgrin by sacrificing Infernal Vessel
5. When Infernal Vessel dies, Luminous Broodmoth triggers, returning Infernal Vessel from your graveyard to the battlefield with a flying counter on it
6. Resolve the Grimgrin ability
7. Repeat

Results

• Infinite +1/+1 counters on a creature
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers