Ok, this one is stumping me so you all have a real hard challenge. This movie I remember having a name like Schizo or something. I just rememeber in my teens I didn't know how to pronounce it. In the film I don't remember seeing the beginning but it dealt with a guy who growing up near an Incan temple made an imaginary friend. The friend was really an Aztec/Incan/Mayan demon posing to him as a little boy. He then gets the guy to kill off some of his old friends when he comes back to the ruins as an adult. I don't remember the details except I though it was a pretty good horror flick back when I was 13/14. The movie was probably from the very early 90s.