Grist, Voracious Larva // Grist, the Plague Swarm | Doubling Season | Body Launderer

(and one other card)

Activate
Phyrexian Altar by sacrificing
Body Launderer, adding ({G} magic symbol) .
When
Body Launderer dies, its second ability triggers, returning
Grist, Voracious Larva from your graveyard to the battlefield.
When
Grist, Voracious Larva enters the battlefield, it triggers, causing you to pay ({G} magic symbol) to exile it and return it to the battlefield as
Grist, the Plague Swarm with six loyalty counters due to
Doubling Season.
Activate
Grist, the Plague Swarm's third loyalty ability by removing six loyalty counters from it.
Grist, the Plague Swarm is put into your graveyard as a state-based action due to having zero loyalty.
Resolve the
Grist, the Plague Swarm ability, creating two token copies of each creature card in your graveyard that is a 1/1 Insect.
Put all but one
Grist, Voracious Larva token into your graveyard due to the legend rule.
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.
Activate
Phyrexian Altar by sacrificing the
Grist, Voracious Larva token, adding one mana of any color.
Repeat from step 1, sacrificing a
Body Launderer token instead.