Activate Altar of Dementia twice by sacrificing Gruff Triplets and Slimefoot and Squee.
When Slimefoot and Squee and Gruff Triplets die, Pitiless Plunderer triggers twice and Gruff Triplets' second ability triggers once.
Resolve the Pitiless Plunderer triggers, creating two Treasure artifact tokens.
Resolve the Gruff Triplets trigger, putting a number of +1/+1 counters equal to Gruff Triplets' power on each creature you control named Gruff Triplets.
Resolve the Altar of Dementia abilities, causing target player to mill cards equal to Gruff Triplets and Slimefoot and Squee's combined power.
Activate two Treasures by tapping and sacrificing them, adding two in any combination of , or .
Activate Slimefoot and Squee by paying 1 and sacrificing a Saproling.
When the creature dies, Pitiless Plunderer triggers, creating a Treasure artifact token.
Resolve the Slimefoot and Squee ability, returning it and Gruff Triplets from your graveyard to the battlefield.
Slimefoot and Squue and Gruff Triplets' second ability triggers.
Resolve the Slimefoot and Squee trigger, creating a 1/1 Saproling creature token.
Resolve the Gruff Triplets trigger, creating two token copes of it.
Activate Altar of Dementia by sacrificing a Gruff Triplets token.
When the Gruff Triplets token dies, Pitiless Plunderer triggers, creating a Treasure artifact token.
Resolve the Altar of Dementia ability, causing target player to mill cards equal to the Gruff Triplets token's power.
Activate two Treasures by tapping and sacrificing them, adding 1.
Repeat.
This loop relies on a brilliant cycle of sacrifice, reanimation, and compounding growth to overwhelm your opponents. By feeding your creatures into Altar of Dementia, you trigger Pitiless Plunderer to generate the Treasure tokens needed to fund Slimefoot and Squee's resurrection ability. Meanwhile, Gruff Triplets provides an exponential burst of power—thanks to its entry tokens and death trigger that beefs up surviving copies—which not only fuels massive mill through Altar of Dementia, but also keeps the token count healthy alongside the Saproling created by Slimefoot and Squee.