How can you create a combo with Thraben Doomsayer, Thornbite Staff, Ashnod's Altar?
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[START OF COMBO]This combo can be formed with Thraben Doomsayer, Thornbite Staff, Ashnod's Altar

Color identity: W
Mana cost: 
Steps:
  1. Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
  2. Activate Ashnod's Altar by sacrificing the Human, adding {C}{C}.
  3. When the Human dies, Thraben Doomsayer triggers, untapping Thraben Doomsayer.
  4. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite leaves the battlefield
  - Infinite enters the battlefield
  - Infinite sacrifice triggers
  - Infinite death triggers
  - Infinite colorless mana
  - Infinite damage[END OF COMBO RESULT][END OF COMBO]

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