How can you create a combo with Spelljack, Bonus Round?
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[START OF COMBO]This combo can be formed with Spelljack, Bonus Round

Color identity: UR
Mana cost: {4}{U}{U}{U}{R}{R} plus enough mana to cast the additional instant card
Steps:
  1. Cast Bonus Round by paying {1}{R}{R}, causing you to copy any instant and/or sorcery spell you cast this turn.
  2. Cast any other instant card from your hand by paying its mana cost.
  3. Bonus Round triggers, copying the instant.
  4. Holding priority, cast Spelljack by paying {3}{U}{U}{U}, targeting the instant.
  5. Bonus Round triggers, creating a copy of Spelljack that is targeting the original Spelljack.
  6. Resolve the copy of Spelljack, countering the original Spelljack and exiling it with the ability to cast it for free from exile.
  7. Cast Spelljack from exile without paying its mana cost, targeting the instant cast in step 1.
  8. Repeat from step 5.[END OF COMBO STEPS]

Result:
  - Infinite magecraft triggers
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be in your hand
  - You have an additional instant card in hand.
[END OF COMBO PREREQUISITES]
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