"What's That Pulling the Carriage?"

In this scene Harry discovers that something is pulling the "horse-less" carriage. This happens on his return to Hogwarts after the Triwizard Tournament. My build displays two scenes. On top is the carriage... but this is no ordinary carriage. A section of the cobblestone road rotates to hide the thestral underneath the platform, revealing an empty section of coblestone. This allows the thestral to be visible from Harry and Luna's perspective but "invisible" to their friends. Underneath, to hide the mechanism and "dissappearing" thestral, is a vignette of the perimeter wall and gate to the castle, which one can see in the distance through the gates.