Ok this has been driving me nuts for over a decade. When I was a kid, I remember watching an animated movie that was in the late 80's/early 90's. All I remember of this movie was that it had a larger than normal horse that the main cahracter and his companions would ride on. The main character's brother carried a sword and seemed to be evil. This brother temporarily joins forces with the group but then leaves on his own sometime in the future. I know it's not a lot to go on but I'm no expert on anime and this film has had a lasting effect on me as well as peak my interest in fantasy since then. Thanks.
-Jim