How can you create a combo with Keiga, the Tide Star, Nim Deathmantle, Pitiless Plunderer, Phyrexian Altar?
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[START OF COMBO]This combo can be formed with Keiga, the Tide Star, Nim Deathmantle, Pitiless Plunderer, Phyrexian Altar

Color identity: UB
Mana cost: 
Steps:
  1. Whenever an opponent controls a creature, activate Phyrexian Altar by sacrificing Keiga, adding {1}.
  2. When Keiga dies, it, Pitiless Plunderer and Nim Deathmantle trigger.
  3. Resolve the Pitiless Plunderer trigger, creating a Treasure artifact token.
  4. Resolve the Keiga trigger, causing you to gain control of a creature an opponent controls.
  5. Activate Phyrexian Altar by sacrificing the creature you gained control of in step 3, adding {1}.
  6. When the creature dies, Pitiless Plunderer triggers, creating a Treasure artifact token.
  7. Activate the Treasures by tapping and sacrificing them, adding {2}.
  8. Resolve the Nim Deathmantle trigger from step 2, causing you to pay {4} to return Keiga from your graveyard to the battlefield, and attach Nim Deathmantle to it.
  9. Repeat as desired and/or whenever a creature enters the battlefield under an opponent's control.[END OF COMBO STEPS]

Result:
  - Gain control of all creatures opponents control and sacrifice them
  - Gain control of any creature that enters the battlefield under an opponent's control[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
[END OF COMBO PREREQUISITES]
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