This TAS beats the game using the potion glitch to skip levels. The potion glitch happens when you die but grab a health potion while dying. The game moves you onto the next level rather than causing you to die.

For more information, see: https://tasvideos.org/8909S
I've also made a video explaining this run here:    • Speedrunner Reviews - Master of Darkn...  

Footage is upscaled to High Definition HD