Ephemerate, Time Stretch, and The Immortal Weapons

Prerequisites

• Ephemerate in hand
• Time Stretch in hand
• The Immortal Weapons on the battlefield
• each other turn available

Steps

1. Cast Time Stretch by paying its mana cost, causing you to take two extra turns after this one
2. Cast Ephemerate by paying , blinking The Immortal Weapons and exiling Ephemerate
3. When The Immortal Weapons enters, it triggers, returning Time Stretch from your graveyard to your hand
4. Move to your next turn
5. At the beginning of your upkeep, Ephemerate's rebound ability triggers, causing you to cast it from exile without paying its mana cost
6. Resolve Ephemerate, blinking The Immortal Weapons
7. When The Immortal Weapons enters, it triggers, returning Ephemerate from your graveyard to your hand
8. Repeat during your second extra turn

Results

• Infinite turns
• Lock