Monk Gyatso, Planar Gate, and Umbral Mantle

Prerequisites

• Monk Gyatso on the battlefield
• Planar Gate on the battlefield
• Umbral Mantle on the battlefield

Steps

1. Activate Umbral Mantle's equip ability by paying , targeting another nontoken creature you control
2. Monk Gyatso triggers, airbending the targeted creature
3. The Umbral Mantle ability fizzles due to no longer having a legal target
4. Cast the creature from exile by paying due to Planar Gate
5. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite storm count