The Mind that Makes the Matter (2000)

This is a psychological journey through the tormented mind of an art student who is summoned to the top of a gothic temple known as the Dreaded Drake Tower. An evil wizard who lives inside the top dome casts a spell on him, which gives him the power to involuntarily manifest horrible things. Whatever he imagines becomes a reality and his own creativeness becomes a doomsday dream which terminates the entire human race.