How can you create a combo with The Tenth Doctor, Dockside Extortionist, Reality Strobe?
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[START OF COMBO]This combo can be formed with The Tenth Doctor, Dockside Extortionist, Reality Strobe

Color identity: UR
Mana cost: {1}{R}
Steps:
  1. Cast Dockside Extortionist by paying {1}{R}.
  2. When Dockside Extortionist enters the battlefield, it triggers, creating at least nine Treasure artifact tokens.
  3. Activate nine Treasures by tapping and sacrificing them, adding {6}{U}{U}{R}.
  4. If Reality Strobe is in your hand, cast it by paying {4}{U}{U}.
  5. Otherwise, activate The Tenth Doctor by paying {7}, causing you to time travel three times, removing all time counters from Reality Strobe and cast Reality Strobe from exile without paying its mana cost.
  6. Resolve Reality Strobe, returning Dockside Extortionist to your hand from the battlefield, and exiling Reality Strobe with three time counters on it.
  7. Repeat.
  8. If opponents control ten or more artifacts and/or enchantments, this combo nets infinite Treasure tokens and mana, and you may bounce other permanents using Reality Strobe.[END OF COMBO STEPS]

Result:
  - Infinite colored mana
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite magecraft triggers
  - Infinite storm count
  - Infinite Treasure tokens
  - Return any number of permanents to their owner's hand[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - The Tenth Doctor must be on the battlefield
  - Dockside Extortionist must be in your hand
  - Reality Strobe must be in your hand or exiled
  - Reality Strobe in hand or exiled with at least one time counter on it.Opponents control at least nine artifacts and/or enchantments.
[END OF COMBO PREREQUISITES]
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