How can you create a combo with Machine God's Effigy, Barrenton Medic?
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[START OF COMBO]This combo can be formed with Machine God's Effigy, Barrenton Medic

Color identity: WU
Mana cost: 
Steps:
  1. Activate Machine God's Effigy by tapping it, adding {U}.
  2. Activate Machine God's Effigy by putting a -1/-1 counter on it, untapping it.
  3. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite blue mana[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
[END OF COMBO PREREQUISITES]
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