How can you create a combo with Clever Impersonator, Mirrormade, Oblivion Ring, Sage of Mysteries?
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[START OF COMBO]This combo can be formed with Clever Impersonator, Mirrormade, Oblivion Ring, Sage of Mysteries

Color identity: WU
Mana cost: {3}{U}{U}{U}{U}
Steps:
  1. Cast Mirrormade by paying {2}{U}.
  2. Mirrormade enters the battlefield as a copy of Oblivion Ring, triggering Sage of Mysteries and itself.
  3. Resolve the Altar of Brood trigger, causing target player to mill two cards.
  4. Resolve the Mirrormade's trigger, exiling Oblivion Ring.
  5. Cast Clever Impersonator by paying {2}{U}{U}.
  6. Clever Impersonator enters the battlefield as a copy of the Oblivion Ring copy, triggering Sage of Mysteries and itself.
  7. Resolve the Altar of Brood trigger, causing target player to mill two cards.
  8. Resolve the Clever Impersonator's trigger, exiling Mirrormade.
  9. Mirrormade leaves the battlefield, triggering itself, returning Oblivion Ring from exile to the battlefield.
  10. Sage of Mysteries and Oblivion Ring trigger.
  11. Resolve the Altar of Brood trigger, causing target player to mill two cards.
  12. Resolve the Oblivion Ring trigger, exiling Clever Impersonator.
  13. Clever Impersonator leaves the battlefield, returning Mirrormade from exile to the battlefield.
  14. Repeat from step 2 until each opponent has an empty library, then end the loop by choosing to copy or exile any other permanent.[END OF COMBO STEPS]

Result:
  - Infinite mill
  - Infinite self-mill[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Clever Impersonator must be in your hand
  - Mirrormade must be in your hand
  - Oblivion Ring must be on the battlefield
  - Sage of Mysteries must be on the battlefield
[END OF COMBO PREREQUISITES]
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