You will Watch Grossology Season 1 Episode 20 online for free episodes with HQ / high quality. Stream cartoons Grossology Episode 20 Silent But Deadly, Part 1. Gassy super villain Fartor returns with a scheme to fart-up the entire planet! But with a plan this big he needs help, and he’s got his sights set on Ty; who, after a falling-out with Abby, turns to the Fart Side.