Subscribe to download
Underground Research Facility

Size: Gigantic! Length: 5+ Hours.
This is a large research facility with several floors to clean. You've only got one incinerator for this map but fortunately it is linked to an garbage shute, allowing you to throw garbage to the lowest level.
Warning: Multiplayer may not work correctly. If you're willing to deal with glitches, you could give it a go. (Clients can attempt to leave the game and re-join it to fix some minor issues like some items/players not appearing for them, and such.)

This map is built to last long, and may take over 5+ hours to complete! I would have recommended to get some friends to speed up this process, but it appears the map is simply too unstable and glitchy in multiplayer, for most people. Using the save function will be your best friend here, you can always return and finish what you started.

Note:
*The Garbage Shute cannot be stained (anymore) by anything that touches it the walls of the shute. But the landing spot can still be stained however.
*Use the white switch near the Incinerator to toggle Anti-Gravity for the Garbage Shute, you could use this for clearing any stuck items or carefully guiding fragile items downwards, or something.
*There's an "anti-gravity net" just above the garbage chute's floor/impact zone. There is no gravity in it, if you see items float above the floor, then they're caught in the anti-gravity net. This is meant to reduce item-stacking lag (although it only reduces it a little). It also affects jumping a little. You cannot turn this off.
*If you are starting to notice FPS lag after dumping garbage, you probably overstuffed the garbage shute area and the item physics are lagging your game, so you should clean that up before continuing.
*Due to the incredible amount of blood splatters and other decals (roughly 1500 of em), and over 1500 or so items, multiplayer has proven to be glitchy, if not unplayable. Try this at your own risk.