Erratic Portal + Karn, Silver Golem + Mirrorworks + Ugin's Nexus

Mana needed: {9} each turn

C identity

Commander legal

The 4 combo pieces

How to execute it

  1. Cast Ugin's Nexus by paying {5}.
  2. When Ugin's Nexus enters, Mirrorworks triggers, causing you to pay {2} to create a token copy of Ugin's Nexus.
  3. Put the token Ugin's Nexus into exile due to the legend rule and its replacement effect, causing you to take an extra turn after this one.
  4. Activate Karn by paying {1}, causing Ugin's Nexus to become a creature until end of turn.
  5. Activate Erratic Portal by paying {1} and tapping it, choosing not to pay and return Ugin's Nexus from the battlefield to your hand.
  6. Repeat each turn.

What the combo produces