How can you create a combo with Grist, Voracious Larva // Grist, the Plague Swarm, Doubling Season, Body Launderer, Phyrexian Altar?
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[START OF COMBO]This combo can be formed with Grist, Voracious Larva // Grist, the Plague Swarm, Doubling Season, Body Launderer, Phyrexian Altar

Color identity: BG
Mana cost: 
Steps:
  1. Activate Phyrexian Altar by sacrificing Body Launderer, adding {G}.
  2. When Body Launderer dies, its second ability triggers, returning Grist, Voracious Larva from your graveyard to the battlefield.
  3. When Grist, Voracious Larva enters the battlefield, it triggers, causing you to pay {G} to exile it and return it to the battlefield as Grist, the Plague Swarm with six loyalty counters due to Doubling Season.
  4. Activate Grist, the Plague Swarm's third loyalty ability by removing six loyalty counters from it.
  5. Grist, the Plague Swarm is put into your graveyard as a state-based action due to having zero loyalty.
  6. Resolve the Grist, the Plague Swarm ability, creating two token copies of each creature card in your graveyard that is a 1/1 Insect.
  7. Put all but one Grist, Voracious Larva token into your graveyard due to the legend rule.
  8. When the Grist, Voracious Larva tokens enters the battlefield, they each trigger for each token created this way. Choose not to pay for any of the triggers.
  9. Activate Phyrexian Altar by sacrificing the Grist, Voracious Larva token, adding one mana of any color.
  10. Repeat from step 1, sacrificing a Body Launderer token instead.[END OF COMBO STEPS]

Result:
  - Infinite leaves the battlefield
  - Infinite enters the battlefield
  - Infinite colored mana
  - Infinite sacrifice triggers
  - Infinite death triggers
  - Infinite creature tokens
  - Infinite copies of creature cards in your graveyard that are 1/1 Insects[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Grist, Voracious Larva // Grist, the Plague Swarm must be in the graveyard
  - Doubling Season must be on the battlefield
  - Body Launderer must be on the battlefield
  - Phyrexian Altar must be on the battlefield
[END OF COMBO PREREQUISITES]
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