Havengul Lich, Grimgrin, Corpse-Born, Headless Rider, and Cryptolith Rite

Prerequisites

• Havengul Lich on the battlefield
• Grimgrin, Corpse-Born on the battlefield
• Headless Rider on the battlefield
• Cryptolith Rite on the battlefield

Steps

1. Activate Grimgrin's ability from Cryptolith Rite by tapping Grimgrin, adding one mana
2. Activate Grimgrin by sacrificing the Zombie castable for one mana, untapping Grimgrin and putting a +1/+1 counter on it
3. When that creature dies, Headless Rider triggers, creating a creature token or a token that adds mana
4. Activate Grimgrin's ability from Cryptolith Rite by tapping Grimgrin, adding one mana
5. Activate Grimgrin by sacrificing the creature token, untapping Grimgrin and putting a +1/+1 counter on it
6. Activate Havengul Lich by paying , allowing you to cast the sacrificed Zombie from your graveyard this turn
7. Cast that Zombie from your graveyard by paying one mana
8. Repeat

Results

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