You find yourself standing in the center of a broad, circular room, the walls, floor and domed ceiling made of a strange stone-like substance of an off-white color. In front of you is what appears to be a very large door, made of the same material as everything else, slightly ajar. Next to the door is a silver sphere, hovering a few inches from the ground to the right. It is repeating a message over and over again, the surface vibrating softly as it radiates sound. The voice sounds high, as though spoken by a small child, but is perfectly clear and easy to understand.
"Welcome to the Interdimensional Nexus. Please proceed through the door and into the common house; everything will be explained there. We request that you refrain from violence here. It is not appreciated and will be dealt with harshly."
With no other choice, you step through the door and into a massive room, the floor of the same off-white stone but the walls and ceiling made of various types of wood, arranged in no particular pattern but well-assembled and smoothed. The ceiling is almost fifty feet up, and opposite you is another door, the same size as the first, with smaller doors built in at the base. The large main door is closed, though the smaller doors are open, though it's too bright outside to see anything from where you stand.
Various broad rugs are set about on the floor of this room, and a broad variety of seats and tables and other such furniture is set up in bunches throughout, most of them centered around broad fire-pits made of stone and metal and set atop the white-stone floor. Along the walls hang various little decorations, and the entire right wall is occupied by a long, well-polished and somewhat worn bar with stools placed along its entire length, getting taller on one end with a ramp behind it for the bartender. In the far left corner is a broad, zig-zagging staircase leading to walkways along the left wall every ten feet or so up toward the ceiling, with doorways spaced evenly along each level. Some of them are open, revealing what seems to be some sort of housing within, akin to hotel rooms.
Another metallic sphere hovers just in front of you, lifting off of the ground as you step through the doorway. The voice from this one is far lower, and very solemn.
Welcome to the Nexus. From here, it's all up to you.