For those not familiar with Animaniacs, the Void-modified version of the premise is as follows:

Set (in the most general of ways) in a train yard in a modern system, a large cast of transforming voidcraft and their staff perform skits featuring dramatics, comedy, singing, and social commentary relevant to issues that were current in the system in which it aired. The trains like doing their work, but they also like causing trouble, and the staff have their hands full with twelve of the rowdy things! "And we're supposed to be the smallest class!"