Karn, the Great Creator, Displacer Kitten, Ugin's Nexus, and Krark-Clan Ironworks

Prerequisites

• Karn, the Great Creator on the battlefield
• Displacer Kitten on the battlefield
• Ugin's Nexus on the battlefield
• Krark-Clan Ironworks on the battlefield
• Karn has at least three loyalty counters
• on each extra turn available

Steps

1. Activate Krark-Clan Ironworks by sacrificing Ugin's Nexus, adding
2. Ugin's Nexus is exiled instead of being put into your graveyard, causing you to take an extra turn after this one
3. Activate Karn's second ability by removing two loyalty counters from it, putting Ugin's Nexus into your hand from exile
4. Move to your next turn
5. Cast Ugin's Nexus by paying
6. Displacer Kitten triggers, blinking Karn
7. Repeat

Results

• Infinite turns