How can you create a combo with Heidar, Rimewind Master, Parallax Tide, Retreat to Coralhelm, Caged Sun?
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[START OF COMBO]This combo can be formed with Heidar, Rimewind Master, Parallax Tide, Retreat to Coralhelm, Caged Sun

Color identity: U
Mana cost: 
Steps:
  1. Activate four Islands by tapping them, adding {U}{U}{U}{U}.
  2. Caged Sun triggers, adding {U}{U}{U}{U}.
  3. Cast Parallax Tide by paying {2}{U}{U}.
  4. Activate Parallax Tide four times by removing four fade counters from it, exiling the four tapped Islands.
  5. Activate Heidar by paying {2} and tapping it, returning Parallax Tide from the battlefield to your hand.
  6. When Parallax Tide leaves the battlefield, it triggers, returning all cards exiled with it to the battlefield.
  7. When the Islands enter the battlefield, Retreat to Coralhelm triggers four times, untapping Heidar, and allowing you to untap up to three other creatures you control and/or scry 1 up to three times.
  8. Repeat from step 2.[END OF COMBO STEPS]

Result:
  - Infinite blinking of lands you control
  - Infinite landfall triggers
  - Infinite mana basic lands you control can produce
  - Infinite mana creatures you control can produce
  - Infinite scry 1
  - Infinite storm count
  - Infinite untap of creatures you control[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Heidar, Rimewind Master must be on the battlefield
  - Parallax Tide must be in your hand
  - Retreat to Coralhelm must be on the battlefield
  - Caged Sun must be on the battlefield
  - You control at least four untapped Islands.
  - Heidar does not have summoning sickness.
  - You control at least four snow permanents.
  - "Blue" chosen with Caged Sun.
[END OF COMBO PREREQUISITES]
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