Lightning Crafter, and Molten Echoes

Prerequisites

• Lightning Crafter in hand
• Molten Echoes on the battlefield
• "Goblin" or "Shaman" chosen with Molten Echoes
• available

Steps

1. Cast Lightning Crafter by paying
2. Lightning Crafter enters the battlefield, triggering itself and Molten Echoes
3. Resolve the Molten Echoes trigger, creating a token copy of Lightning Crafter with haste
4. The Lightning Crafter token enters the battlefield, triggering itself
5. In response, activate the Lightning Crafter token by tapping it, dealing 3 damage to any target
6. Resolve the Lightning Crafter token's ability, exiling the nontoken Lightning Crafter
7. When the nontoken Lightning Crafter leaves the battlefield, it triggers itself, having no effect since no card was exiled
8. Resolve the Lightning Crafter trigger from step 2, exiling the token Lightning Crafter
9. When the token Lightning Crafter leaves the battlefield, it triggers itself, returning the nontoken Lightning Crafter from exile to the battlefield
10. Repeat from step 2

Results

• Infinite damage
• Infinite ETB
• Infinite LTB