How can you create a combo with Dockside Extortionist, Fool's Demise, Ashnod's Altar?
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[START OF COMBO]This combo can be formed with Dockside Extortionist, Fool's Demise, Ashnod's Altar

Color identity: UR
Mana cost: 
Steps:
  1. Activate Ashnod's Altar by sacrificing Dockside Extortionist, adding {C}{C}.
  2. Dockside Extortionist dies, triggering Fool's Demise first and second abilities.
  3. Resolve the first Fool's Demise trigger, returning Dockside Extortionist from your graveyard to the battlefield.
  4. Dockside Extortionist enters the battlefield, creating at least four Treasure tokens.
  5. Resolve the second Fool's Demise trigger, returning it from your graveyard to your hand.
  6. Activate three Treasure tokens by tapping and sacrificing them, adding {2}{U}.
  7. Cast Fool's Demise by paying {4}{U}, attaching it to Dockside Extortionist.
  8. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite colored mana
  - Infinite colorless mana
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite sacrifice triggers
  - Infinite storm count
  - Infinite Treasure tokens[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Fool's Demise attached to Dockside Extortionist.
  - Opponents control at least four artifacts and/or enchantments.
[END OF COMBO PREREQUISITES]
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