How can you create a combo with Mairsil, the Pretender, Mirror-Mad Phantasm, Thassa's Oracle?
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[START OF COMBO]This combo can be formed with Mairsil, the Pretender, Mirror-Mad Phantasm, Thassa's Oracle

Color identity: UBR
Mana cost: {1}{U}{U}{U}
Steps:
  1. Activate Mairsil using Mirror-Mad Phantasm's ability by paying {1}{U}, putting your entire library into your graveyard.
  2. Cast Thassa's Oracle by paying {U}{U}.
  3. Thassa's Oracle enters the battlefield, winning you the game.[END OF COMBO STEPS]

Result:
  - Win the game[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Mairsil, the Pretender must be on the battlefield
  - Mirror-Mad Phantasm must be exiled
  - Thassa's Oracle must be in your hand
  - Mirror-Mad Phantasm exiled with a cage counter on it.
[END OF COMBO PREREQUISITES]
assistant