God-Eternal Kefnet, Isochron Scepter, Brainstorm, and Time Warp

Prerequisites

• God-Eternal Kefnet on the battlefield
• Isochron Scepter on the battlefield
• Brainstorm in exile
• Time Warp in hand
• plus available each other turn available

Steps

1. During the end step before your turn, activate Isochron Scepter by paying and tapping it, casting a copy of Brainstorm without paying its mana cost
2. Resolve Brainstorm, causing you to draw three cards and put Time Warp and another card on top of your library, ensuring Time Warp is the topmost card
3. Move to your turn, drawing and revealing Time Warp during your draw step
4. God-Eternal Kefnet's first ability triggers, causing you to pay to cast a copy of Time Warp
5. Resolve the copy of Time Warp, causing you to take an extra turn after this one
6. Activate Isochron Scepter by paying and tapping it, casting a copy of Brainstorm without paying its mana cost
7. Repeat from step 2

Results

• Infinite turns