Karn, the Great Creator + Ugin's Nexus + Throne of Geth + Inexorable Tide

Prerequisites

• Karn has at least two loyalty counters on it.

Steps

1. 1Activate Throne of Geth by tapping it and sacrificing Ugin's Nexus.
2. 2Ugin's Nexus is exiled instead of being put into your graveyard, causing you to take an extra turn after this one.
3. 3Resolve the Throne of Geth ability, putting a loyalty counter on Karn.
4. 4Activate Karn's second loyalty ability by removing two loyalty counters from it, returning Ugin's Nexus from exile to your hand.
5. 5Move to your next turn.
6. 6Cast Ugin's Nexus by paying .
7. 7Inexorable Tide triggers, putting a loyalty counter on Karn.
8. 8Repeat.

Effects

• Infinite turns
• Lock