Molten Echoes, and Worldgorger Dragon

Prerequisites

• Molten Echoes on the battlefield
• Worldgorger Dragon in hand
• "Dragon" chosen with Molten Echoes
• available

Steps

1. Cast Worldgorger Dragon, triggering Molten Echoes and Worldgorger Dragon's ETBs; stack the triggers to resolve in that order
2. Resolve Molten Echoes' trigger, creating a token copy of Worldgorger Dragon and triggering its ETB
3. Float as much mana as you want in response to the token's ETB trigger
4. The token's effect resolves, exiling everything else you control, including the original Worldgorger Dragon
5. Resolve the original Worldgorger Dragon's LTB with no effect, then resolve the ETB trigger of the original Worldgorger Dragon, exiling the token copy
6. Resolve token Worldgorger Dragon's LTB trigger, returning everything it exiled to the battlefield under your control
7. Name Dragons as Molten Echoes enters the battlefield
8. Repeat the loop from the top for infinite mana
9. Repeat this process until you have infinite mana
10. The loop can broken by naming a different creature type as Molten Echoes enters the battlefield

Results

• Infinite blinks of all permanents you control
• Infinite colored mana
• Infinite ETB
• Infinite LTB