Upon defeating the Black Knight on Advanced he falls back into his chair, then turns into a little swirling ball of energy, and flies up the place where his drinks were coming from. Prince Duncan then goes to the fireplace, and pulls on the torch, and is taken back to the Main Menu. This time, after doing his victory dance, the Energy ball that the Black Knight turned into comes from the top of the screen, and turns Duncan into the Black Knight. The new Black Knight then looks at himself, and the wall turns around, showing a "The End" on the other side.
Unlike the original Dark Castle beating the game on advanced doesn't reset it, meaning that you cannot try again and again for a high score, making some hardcore fans disappointed.
- Video of the ending *spoilers*