How can you create a combo with Chthonian Nightmare, Priest of Gix, Priest of Urabrask?
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[START OF COMBO]This combo can be formed with Chthonian Nightmare, Priest of Gix, Priest of Urabrask

Color identity: BR
Mana cost: 
Steps:
  1. Activate Chthonian Nightmare by paying {E}{E}{E}, sacrificing Priest of Urabrask and returning Chthonian Nightmare from the battlefield to your hand, returning Priest of Gix from your graveyard to the battlefield.
  2. When Priest of Gix enters the battlefield, it triggers, adding {B}{B}{B}.
  3. Cast Chthonian Nightmare by paying {1}{B}.
  4. When Chthonian Nightmare enters the battlefield, it triggers, causing you to get {E}{E}{E}.
  5. Activate Chthonian Nightmare by paying {E}{E}{E}, sacrificing Priest of Gix and returning Chthonian Nightmare from the battlefield to your hand, returning Priest of Urabrask from your graveyard to the battlefield.
  6. When Priest of Urabrask enters the battlefield, it triggers, adding {R}{R}{R}.
  7. Cast Chthonian Nightmare by paying {1}{B}.
  8. When Chthonian Nightmare enters the battlefield, it triggers, causing you to get {E}{E}{E}.
  9. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite black mana
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite red mana
  - Infinite sacrifice triggers
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Chthonian Nightmare must be on the battlefield
  - Priest of Gix must be in the graveyard
  - Priest of Urabrask must be on the battlefield
  - You have at least three energy counters.
[END OF COMBO PREREQUISITES]
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