How can you create a combo with Orvar, the All-Form, Spark Double, Clockspinning?
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[START OF COMBO]This combo can be formed with Orvar, the All-Form, Spark Double, Clockspinning

Color identity: U
Mana cost: {9}{U}{U}{U}
Steps:
  1. Cast Clockspinning with buyback by paying {3}{U}, targeting Spark Double.
  2. Orvar triggers, creating a token copy of Spark Double that enters the battlefield as a nonlegendary token copy of Orvar.
  3. Resolve Clockspinning, returning it to your hand.
  4. Cast Clockspinning with buyback by paying {3}{U}, targeting Spark Double.
  5. Orvar and the Spark Double token trigger, creating two token copies of Spark Double that enters the battlefield as a nonlegendary token copy of Orvar.
  6. Resolve Clockspinning, returning it to your hand.
  7. Cast Clockspinning with buyback by paying {3}{U}, targeting any Island that enters the battlefield untapped.
  8. Orvar, Spark Double and the three Spark Double tokens trigger, creating five token copies of the Island.
  9. Resolve Clockspinning, returning it to your hand.
  10. Activate four of the Island tokens by tapping them, adding {U}{U}{U}{U}.
  11. Repeat from step 7.
  12. Once you have infinite mana, you can then target any permanent using Clockspinning to get infinite tokens of them.[END OF COMBO STEPS]

Result:
  - Infinite copies of permanents you control
  - Infinite creature tokens
  - Infinite enters the battlefield
  - Infinite landfall triggers
  - Infinite magecraft triggers
  - Infinite mana lands you control can produce
  - Infinite proliferate
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Orvar, the All-Form must be on the battlefield
  - Spark Double must be on the battlefield
  - Clockspinning must be in your hand
  - You control an Island that enters the battlefield untapped.
[END OF COMBO PREREQUISITES]
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