Abuelo, Ancestral Echo + Ugin's Nexus + Mirrorworks

Prerequisites

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Steps

1. 1Activate Abuelo by paying , exiling Ugin's Nexus until the beginning of the next end step.
2. 2At the beginning of your end step, Abuelo triggers, returning Ugin's Nexus from exile to the battlefield.
3. 3When Ugin's Nexus enters the battlefield, Mirrorworks triggers, causing you to pay to create a token copy of Ugin's Nexus.
4. 4Put 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.
5. 5Activate Abuelo by paying , exiling Ugin's Nexus until the beginning of the next end step.
6. 6Move to your next turn, not skipping it as Ugin's Nexus is not on the battlefield.
7. 7Repeat from step 2.

Effects

• Infinite turns
• Lock