How can you create a combo with Urza, Prince of Kroog, Metalworker, Retreat to Coralhelm, Razortide Bridge?
user
[START OF COMBO]This combo can be formed with Urza, Prince of Kroog, Metalworker, Retreat to Coralhelm, Razortide Bridge

Color identity: WU
Mana cost: 
Steps:
  1. Activate Metalworker by tapping it and revealing at least three artifact cards from your hand, adding at least six {C}.
  2. Activate Urza by paying {6}, creating a token copy of Razortide Bridge that is a 1/1 Soldier.
  3. When the Razortide Bridge token enters the battlefield, Retreat to Coralhelm triggers, untapping Metalworker.
  4. Repeat.
  5. If you have four or more artifact cards in hand, this combo nets infinite colorless mana, and you may target any artifact you control to get infinite copies of them.[END OF COMBO STEPS]

Result:
  - Infinite colorless mana
  - Infinite copies of each artifact you control
  - Infinite creature tokens
  - Infinite enters the battlefield
  - Infinite landfall triggers[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - You have at least three artifact cards in hand.
  - Metalworker does not have summoning sickness.
[END OF COMBO PREREQUISITES]
assistant