Leonin Relic-Warder, and Phyrexian Metamorph

Prerequisites

• Leonin Relic-Warder on the battlefield
• Phyrexian Metamorph in hand
• available

Steps

1. Have Metamorph enter the battlefield, choosing to have it enter as Relic-Warder
2. Target Metamorph with the copied Relic-Warder Trigger
3. The Metamorph Relic-Warder exiles itself, then the second trigger returns it to the battlefield
4. Repeat steps 1-3

Results

• Infinite ETB
• Infinite LTB