Toph, the First Metalbender, Mycosynth Lattice, and Yahenni, Undying Partisan

Prerequisites

• Toph, the First Metalbender on the battlefield
• Mycosynth Lattice on the battlefield
• Yahenni, Undying Partisan on the battlefield
• plus the cost of the creature that earthbends available

Steps

1. Cast the earthbending creature by paying its mana cost, causing it to enter as an artifact land creature due to Mycosynth Lattice and Toph
2. When that creature enters, it earthbends, causing itself to become a land creature with haste, putting at least one +1/+1 counter on itself, and creating a delayed triggered ability
3. Activate Yahenni by sacrificing that creature
4. When that creature dies, the delayed ability from step 2 triggers, causing it to return to the battlefield tapped as an artifact land creature
5. Repeat from step 2 any number of times
6. Resolve all activated abilities from Yahenni

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite landfall triggers
• Infinite sacrifice triggers