How can you create a combo with Rootha, Mercurial Artist, Dramatic Reversal, Winding Canyons?
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[START OF COMBO]This combo can be formed with Rootha, Mercurial Artist, Dramatic Reversal, Winding Canyons

Color identity: UR
Mana cost: {1}
Steps:
  1. Activate all mana-producing nonland permanents you control by tapping them, adding at least {3}{U}{R}.
  2. Activate Winding Canyons's second ability by paying {2} and tapping it, allowing you to cast creature spells this turn as though they had flash.
  3. Cast Dramatic Reversal by paying {1}{U}.
  4. Activate Rootha by paying {2} and returning it to your hand, copying Dramatic Reversal.
  5. Resolve the Dramatic Reversal copy, untapping all nonland permanents you control.
  6. Activate all mana-producing nonland permanents you control by tapping them, adding at least {3}{U}{R}.
  7. Cast Rootha by paying {1}{U}{R}.
  8. Repeat from step 4.
  9. If nonland permanents you control can tap to produce at least {4}{U}{R}, this combo nets infinite mana.[END OF COMBO STEPS]

Result:
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite magecraft triggers
  - Infinite mana nonland permanents you control can produce
  - Infinite storm count
  - Infinite untap of nonland permanents you control[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Rootha, Mercurial Artist must be on the battlefield
  - Dramatic Reversal must be in your hand
  - Winding Canyons must be on the battlefield
  - Nonland permanents you control can tap to produce at least {3}{U}{R}.
[END OF COMBO PREREQUISITES]
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