How can you create a combo with Urza, Prince of Kroog, Dockside Extortionist, Liquimetal Coating?
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[START OF COMBO]This combo can be formed with Urza, Prince of Kroog, Dockside Extortionist, Liquimetal Coating

Color identity: URW
Mana cost: {6}
Steps:
  1. Activate Liquimetal Coating by tapping it, causing Dockside Extortionist to become an artifact until end of turn.
  2. Activate Urza by paying {6}, creating a token copy of Dockside Extortionist that is a 1/1 Soldier in addition to its other types.
  3. The Dockside Extortionist token enters the battlefield, creating at least seven Treasure tokens.
  4. Activate six Treasure tokens by tapping and sacrificing them, adding {6}.
  5. Repeat from step 2.
  6. Once you have infinite mana and Treasure tokens, you may use Urza to make infinite copies of any artifacts you control.[END OF COMBO STEPS]

Result:
  - Infinite colored mana
  - Infinite copies of artifacts you control
  - Infinite creature tokens
  - Infinite enters the battlefield
  - Infinite Treasure tokens[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Opponents control at least seven artifacts and/or enchantments.
[END OF COMBO PREREQUISITES]
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