Thread:TheLastHappyPotato/@comment-35195751-20190621011914/@comment-28692716-20191014235903

The key has 710 engraved in it. On the desk is a note saying "Don't lose it." The door is locked, although the locking mechanism is on your side, meaning the key would go in from the outside.

Outside, you see a fairly open room, many more doors like the one you opened around. Meanwhile, you can see sentient slimes waiting in the corners of the room, and an armored man with a large spear standing by a stairwell, and a similar man standing by what looked like an elevator.