How can you create a combo with Royal Assassin, Orb of Dreams, Thornbite Staff?
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[START OF COMBO]This combo can be formed with Royal Assassin, Orb of Dreams, Thornbite Staff

Color identity: B
Mana cost: 
Steps:
  1. Whenever a creature enters the battlefield under an opponent's control, it enters tapped due to Orb of Dreams.
  2. Holding priority, activate Royal Assassin by tapping it, destroying the creature.
  3. The creature dies, triggering Royal Assassin, untapping Royal Assassin.
  4. Repeat.[END OF COMBO STEPS]

Result:
  - Destroy all creatures that enter the battlefield under an opponent's control[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Royal Assassin does not have summoning sickness.
  - Thornbite Staff attached to Royal Assassin.
[END OF COMBO PREREQUISITES]
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