Animated Movie Help please?
Hey i cannot remember the name of an animated movie that i watched about 10 years ago with a blue teenager who is the brother or somehow is friends with the protagonist, but he becomes this bad magician but at the end dies i believe saving a good guys life or something

It had a teenage magician who i believe wore a blue outfit, i remember he got killed in the movie there was also a unicorn or something perhaps, any guesses? It probably came out in the late 1980s or early 1990s but im not for certain