The boss door.

As you run through the dungeon, you're puzzled to find an odd lack of monsters. However once you come across some fresh corpses that have yet to despawn, you figure out that it's been cleared out recently. There's an urge to turn back in fear of encountering the heroes that did it, but you press on. Anything that's not the prison of your restricted dungeon area is certainly worth a single ****. Especially considering to how many times you've been killed in all your time here.

Eventually you stop at an imposing, ornate double door of dark wood and steel. It has two doorknockers made to look like they're being held by demonic metal faces, not particularly original. However to you it's possibly the most exciting thing you've ever seen. Given the door's distinct and glamorous look compared to the other doors you've seen, you suspect that it leads to the boss room.

The sound of combat on the other side of the door strengthens this theory. The party that killed its way through the dungeon must be engaged in a fight with the boss. That's when you realize that you've never actually met your boss. You wonder if higher-level monsters get to talk to him, or her, or it, let alone know what kind of boss it is. A mage? A lich? A hulking knight? A dragon?

You feel an itch to open the door. Maybe you could get an opportunity to talk to your boss about your place in the dungeon, perhaps get a quest for a promotion or something? Of course, since your boss was presumably the one to establish the restrictions in the dungeon you'd most likely only be met with anger for leaving your area. But even then, you could at least take a peek to see who it is, maybe watch the battle and learn some tricks...