"Yeah." She nods. "I'm not sure how the rig gets its water, yet - there's a few options I can think of - but that pipe is part of the system. Each floor has at least one central corridor that everything else is off of. And they always have the big water main running along the top. Maybe it's different other places, I dunno, we're not allowed everywhere."

She points at a heavy metal door, set in a frame with complex electronic locks. "Speaking of. That's one of the Forbidden Doors. They're off limits, in a very serious way. Can't hack them or break them, it's been tried. But they make really good landmarks. And those," now she's indicating a puke-green metal door with slits at face level, "are utility doors. Also make good landmarks. Mostly just cleaning supplies in there, and not the fun kind you can make explosives with."