Enamel Mug

If you're referring to a "mug of mud slinger getting dirty," it could describe a scene involving an off-road dirt bike rider or a truck tearing through the mud. Here's a vivid take:

The mud slinger roars to life, tires spinning wildly as it tears through the rugged terrain. Thick clumps of earth spray in every direction, coating the rider from head to toe in a slick, brown layer of filth. The once-pristine machine is now a canvas of grime, its original color barely visible beneath the layers of caked-on mud. With each twist of the throttle, the engine growls, sending another wave of dirt skyward. It's a messy, reckless ride—but for the mud slinger, it's just another day of kicking up chaos.

Does this fit what you're looking for, or do you have a different interpretation in mind?