Activate Selvala by paying and tapping it, adding at least 1.
Activate Viscera Seer twice by sacrificing Selvala and Slimefoot and Squee.
Activate Slimefoot and Squee by paying 1 and sacrificing a Saproling, returning it and Selvala from your graveyard to the battlefield.
When Slimefoot and Squee enters the battlefield, it triggers, creating a 1/1 Saproling creature token.
Repeat.
This loop uses Slimefoot and Squee as a recurring engine that brings itself and Selvala, Heart of the Wilds straight back from the graveyard, fueled by the mana Selvala can tap to produce. Viscera Seer acts as the necessary sacrifice outlet to send your legends back to the graveyard while letting you sculpt your draws along the way, and the Saproling token created upon Slimefoot and Squee's entry provides the exact fodder needed to pay the activation cost. Meanwhile, Tannuk, Steadfast Second sits on the board granting your team haste so everything moves at a rapid pace.