How can you create a combo with Commander Liara Portyr, Eternal Scourge, Ashnod's Altar, Mimic Vat?
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[START OF COMBO]This combo can be formed with Commander Liara Portyr, Eternal Scourge, Ashnod's Altar, Mimic Vat

Color identity: RW
Mana cost: 
Steps:
  1. Declare at least two creatures you control as attackers, attacking at least two opponent.
  2. Liara triggers, causing all spells you cast from exile this turn to cost at least {2} less, and exiling at least two cards from the top of your library and allowing you to play them this turn.
  3. Move to your post-combat main phase.
  4. Activate Ashnod's Altar by sacrificing Eternal Scourge, adding {C}{C}.
  5. Mimic Vat triggers, exiling Eternal Scourge from your graveyard.
  6. Cast Eternal Scourge from exile by paying {1}.
  7. Repeat from step 4.[END OF COMBO STEPS]

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

Other prerequisites:
  - All permanants must be on the battlefield
  - You control at least two creatures that can attack this turn.
  - You have at least two opponents.
[END OF COMBO PREREQUISITES]
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