Donatello, the Brains, Summoning Station, and Krark-Clan Grunt

Prerequisites

• Donatello, the Brains on the battlefield
• Summoning Station on the battlefield
• Krark-Clan Grunt 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 Krark-Clan Grunt by sacrificing the Mutagen
3. Summoning Station triggers, untapping itself
4. Resolve the Krark-Clan Grunt ability
5. Repeat

Results

• Infinite ETB
• Infinite creature tokens
• Infinitely powerful creature until end of turn