There was a movie I watched when I was younger sometime in the mid 80's about a boy who created this little troll/monster by mixing something in a blender that turned neon blue. He poured it out and it formed into the troll/monster. The troll/monster was his friend and would bring him underground into it's world. I can't remember the name of the movie though. I would appreciate it if someone could help me find the name of the movie.