Two very weird bugs happened to me when trying out the slider's dungeon:
First, I beat three of the bosses, found the door to tyhe final boss and right clicked it. It said that i still needed 3 more keys. So i went looking for one and found the miniboss that looks like a slider. So i was using my gravitite sword to kill it and when i was almost done with him, the sword made him go up. He then got stuck up on a wall, and it stayed there for a few seconds.
Suddenly, it fell off the wall and died, but i recieved no key.
To try to "fix it" i went into creative mode and spawned one other boss and killed it. When i put that keyin the door, it said that in needed -4 keys!
I then spawned 4 more minibosses, gout 4 more keys and inserted them in he door, which finally opened.