Sharuum the Hegemon, and Gigantoplasm

Prerequisites

• Sharuum the Hegemon on the battlefield
• Gigantoplasm in hand
• available

Steps

1. Cast Gigantoplasm by paying
2. Gigantoplasm enters as a copy of Sharuum
3. Put Sharuum into the graveyard due to the legend rule
4. Gigantoplasm triggers, returning Sharuum from your graveyard to the battlefield
5. Put Sharuum into the graveyard due to the legend rule
6. Sharuum enters the battlefield triggers, returning itself from your graveyard to the battlefield
7. Repeat from step 5

Results

• Infinite ETB
• Infinite LTB