Activate Viscera Seer by sacrificing Weaponcraft Enthusiast.
When Weaponcraft Enthusiast dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
When Weaponcraft Enthusiast enters, its fabricate ability triggers, putting a +1/+1 counter on it.
Resolve the Viscera Seer ability.
Repeat.
This clever loop centers around the unique interplay between Isilu, Carrier of Twilight's static grant of persist and Weaponcraft Enthusiast's fabricate ability. Because Isilu, Carrier of Twilight gives your nontoken creatures persist, Weaponcraft Enthusiast keeps returning from the graveyard after being sacrificed to Viscera Seer, while state-based actions immediately cancel out the -1/-1 counter using the +1/+1 counter from its own fabricate trigger. Viscera Seer converts this endless cycle of life and death into infinite scry triggers and sacrifices, perfectly primed by Eirdu, Carrier of Dawn's earlier mana-smoothing and convoke utility to get your engine online.