Isochron Scepter, Energy Arc, and Donatello, Mutant Mechanic

Prerequisites

• Isochron Scepter on the battlefield
• Energy Arc in exile
• Donatello, Mutant Mechanic on the battlefield

Steps

1. Animate Isochron Scepter using Donatello
2. Activate any number of creatures by tapping them, adding at least
3. Activate Isochron Scepter by paying and tapping it, casting a copy of Energy Arc without paying its mana cost
4. Resolve Energy Arc, untapping all creatures you control Repeat from step 2

Results

• Infinite magecraft triggers
• Infinite mana creatures you control can produce
• Infinite storm count
• Infinite untap of creatures you control