You already have everything you need
Look back at what's actually in your hands: a hash function and fbm from Module 05, signed distance fields and the "transform the space" trick from Module 04, alpha compositing from Module 07, palettes from Module 03, one-point reflection from Module 06. Every real shader you'll ever see in a shipped game is just some combination of these same handful of ideas, applied with taste. That's not a metaphor — go look at the source of any shader on godotshaders.com and you'll recognize the pieces.
There's no starter/solution pair this time. Pick one of the three references below to load a small scaffold — a few helper functions, a mostly-empty main(), and a comment describing the target. From there, it's genuinely open-ended: experiment, break it, look back at earlier modules when you get stuck, and see how close you can get.
Three real references to chase
Dissolve-death effect — a character crumbling into embers and disappearing, the same family as Module 07's dissolve but applied to a shape mask instead of a sprite's alpha channel.
Shoreline shimmer — light catching moving water near a beach, built from layered noise shifting over time.
Toon outline — a bold dark border around a flat-shaded shape, the cel-shaded look from a hundred stylized indie games.