Contagion Engine + Encroaching Mycosynth + Idris, Soul of the TARDIS + Medomai the Ageless

Mana needed: {1}{U}{R} available the first turn, with {4} each even-numbered extra turn

URW identity

Commander legal

The 4 combo pieces

What must be in place

An opponent cannot block creatures you control.

How to execute it

  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}{U}{R}.
  4. When Idris enters the battlefield, it triggers, exiling Medomai the Ageless until Idris leaves the battlefield.
  5. Move to your extra turn.
  6. At the beginning of your upkeep, Idris's vanishing ability triggers, removing a time counter from it.
  7. Deal combat damage to an opponent using Idris.
  8. Idris triggers, causing you to take an extra turn after this one.
  9. Repeat steps 5 through 8 one additional time.
  10. Activate Contagion Engine by paying {4} and tapping it, putting two time counters on Idris.
  11. Repeat from step 5.

What the combo produces