Donatello, the Brains, Summoning Station, and Umbral Collar Zealot

Prerequisites

• Donatello, the Brains on the battlefield
• Summoning Station on the battlefield
• Umbral Collar Zealot on the battlefield

Steps

1. Activate Summoning Station by tapping it, creating a 2/2 Pincher creature token and a Mutagen token due to Donatello
2. Activate Umbral Collar Zealot by sacrificing the Mutagen
3. Summoning Station triggers, untapping itself
4. Resolve the Umbral Collar Zealot ability
5. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite creature tokens
• Infinite death triggers
• Infinite sacrifice triggers
• Infinite surveil