How can you create a combo with Medomai the Ageless, Preeminent Captain, Arcane Adaptation, Erratic Portal?
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[START OF COMBO]This combo can be formed with Medomai the Ageless, Preeminent Captain, Arcane Adaptation, Erratic Portal

Color identity: WU
Mana cost: 
Steps:
  1. Declare Preeminent Captain as an attacker.
  2. Preeminent Captain triggers, putting Medomai from your hand onto the battlefield tapped and attacking.
  3. Deal combat damage with Medomai, causing you to take an extra turn after this one.
  4. Activate Erratic Portal by paying {1} and tapping it, returning Medomai to your hand.
  5. Pass the turn.
  6. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite turns[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - "Samurai" chosen with Arcane Adaptation.
  - Oathkeeper attached to Filigree Familiar.
[END OF COMBO PREREQUISITES]
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