Kiki-Jiki, Mirror Breaker, Cacophodon, and Aether Flash

Prerequisites

• Kiki-Jiki, Mirror Breaker on the battlefield
• Cacophodon on the battlefield
• Aether Flash on the battlefield

Steps

1. Activate Kiki-Jiki by tapping it, creating a token copy of Cacophodon with haste
2. The Cacophodon token enters the battlefield, triggering Aether Flash, dealing 2 damage to the Cacophodon token
3. The Cacophodon token triggers, untapping Kiki-Jiki
4. Repeat

Results

• Infinite creature tokens with haste
• Infinite ETB