Emrakul, the Promised End, Erratic Portal, Unwinding Clock, and Vedalken Orrery

Prerequisites

• Emrakul, the Promised End in hand
• Erratic Portal on the battlefield
• Unwinding Clock on the battlefield
• Vedalken Orrery on the battlefield
• You control artifacts that can produce enough mana to cast Emrakul, plus an additional

Steps

1. Cast Emrakul by paying reduced by its first ability
2. Emrakul's second ability triggers, causing you to gain control of an opponent's next turn and giving them an additional turn after that one
3. Move to that opponent's next turn
4. Unwinding Clock triggers, untapping all artifacts you control
5. Activate artifacts by tapping them to add enough mana to cast Emrakul, plus an additional
6. Activate Erratic Portal by paying and tapping it, returning Emrakul from the battlefield to your hand
7. Repeat until the opponent you are controlling each extra turn has lost the game
8. Repeat for each remaining opponent

Results

• Infinite turns for each opponent
• You control your opponents on each of their turns