How can you create a combo with Sakashima of a Thousand Faces, Hellkite Courser, Altar of Dementia?
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[START OF COMBO]This combo can be formed with Sakashima of a Thousand Faces, Hellkite Courser, Altar of Dementia

Color identity: UR
Mana cost: {3}{U} plus enough mana to pay for commander tax, if applicable
Steps:
  1. Cast Sakashima either from your hand or from the command zone by paying {3}{U} and commander tax, if applicable.
  2. Choose to have Sakashima enter the battlefield as a copy of Hellkite Courser.
  3. Sakashima enters the battlefield, triggering its ability.
  4. Holding priority, activate Altar of Dementia by sacrificing Sakashima.
  5. Choose to return Sakashima to the command zone from your graveyard.
  6. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Sakashima's power.
  7. Resolve the Sakashima trigger from step 3, putting Sakashima from the command zone onto the battlefield.
  8. Repeat from step 2.[END OF COMBO STEPS]

Result:
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite mill
  - Infinite sacrifice triggers
  - Infinite self-mill[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Sakashima of a Thousand Faces must be in your hand or in the command zone
  - Hellkite Courser must be on the battlefield
  - Altar of Dementia must be on the battlefield
  - Sakashima of a Thousand Faces is one of your commanders.
[END OF COMBO PREREQUISITES]
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