Medomai the Ageless + Idris, Soul of the TARDIS + Jhoira's Timebug + Encroaching Mycosynth

Medomai the Ageless

Idris, Soul of the TARDIS

Jhoira's Timebug

Encroaching Mycosynth

How it works

1. Deal combat damage to an opponent using Medomai the Ageless.
2. Medomai the Ageless triggers, causing you to take an extra turn after this one.
3. Cast Idris by paying 1.
4. When Idris enters the battlefield, it triggers, exiling Medomai the Ageless until Idris leaves the battlefield.
5. Activate Jhoira's Timebug by tapping it, putting a time counter on Idris.
6. Move to your extra turn.
7. At the beginning of your upkeep, Idris's vanishing ability triggers, removing a time counter from it.
8. Deal combat damage to an opponent using Idris.
9. Idris triggers, causing you to take an extra turn after this one.
10. Repeat from step 5.

This clever setup lets you break Medomai the Ageless's dreaded restriction against attacking during extra turns by turning to Idris, Soul of the TARDIS for help. Thanks to Encroaching Mycosynth making all of your nonland permanents into artifacts, Idris can successfully imprint Medomai when it enters the battlefield, absorbing the Sphinx's exact triggered ability to take an extra turn upon dealing combat damage while cleanly bypassing Medomai's built-in clause. To keep Idris from vanishing away too quickly, Jhoira's Timebug steps in to continuously add time counters to Idris during each cycle, ensuring your newly acquired extra turns keep marching on indefinitely.