Activate Viscera Seer 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 Viscera Seer abilities, causing you to scry 1 twice.
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 Viscera Seer by sacrificing a Gruff Triplets token.
When the Gruff Triplets token dies, Pitiless Plunderer triggers, creating a Treasure artifact token.
Resolve the Viscera Seer ability, causing you to scry 1.
Activate two Treasures by tapping and sacrificing them, adding 1.
Repeat.
This elegant cycle revolves around the relentless recursion engine of Slimefoot and Squee, which uses its activated ability to haul itself and Gruff Triplets right back out of the graveyard. Viscera Seer provides the clean sacrifice outlet to send them back to the bin while smoothing your draws with repeated scrys, while Pitiless Plunderer quietly tracks every single death to bank the Treasure tokens needed to fuel Slimefoot and Squee's steep manacost. As these pieces loop endlessly, Gruff Triplets constantly enters anew to multiply its tokens and pump up your board with staggering amounts of +1/+1 counters.