Ghired, Mirror of the Wilds, Thornbite Staff, and Grimgrin, Corpse-Born

Prerequisites

• Ghired, Mirror of the Wilds on the battlefield
• Thornbite Staff on the battlefield
• Grimgrin, Corpse-Born on the battlefield

Steps

1. Activate Ghired by tapping it, creating a token copy of any creature token you control that entered the battlefield this turn
2. Activate Grimgrin by sacrificing the creature token
3. When the token dies, Ghired triggers, untapping itself
4. Resolve the Grimgrin ability, causing target player to mill cards equal to the sacrificed creature's power
5. Repeat
6. Activate Grimgrin by tapping it, creating a token copy of any creature token you control that entered the battlefield this turn
7. Activate Grimgrin by sacrificing the creature token created in step 1, untapping Grimgrin and putting a +1/+1 counter on it
8. Repeat

Results

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