Grayskull Sewer

On Playset Street the Ninja Turtles live next door to Castle Grayskull. And as I was building their new Sewer Lair I began to wonder, if the Sewer Lair goes underground, it must extend down the street, too...right? Does Grayskull have plumbing? What does the sewer under Grayskull look like? And so I built it.

Done