Evil wizard, cavern, immortal, heart, fantasy
It's fantasy movie from 60's, 70's or 80's, perhaps from Soviet Union. My friend saw it in 80's. The main character is a man (perhaps a young boy). His main enemy is an evil wizard. The wizard lives in a cave and keeps his heart. He doesn't leave a cavern. He is immortal (probably).I think that main weakness of the wizard was his heart and it was reason that wizard keeps own heart. At the end, the main character destroy his heart, when a wizard leaves a grotto. The wizard rides and falls from horse and die (something like heart attack).
It's similar thread like "Captain Sindbad" (1963), but it isn't.
Definitely not:
Kashchey the Immortal, Russian Кащей Бессмертный, 1945 B&W fantasy directed by Alexander Rou, with Georgy Millyar as Koschei.
Fire, Water, and Brass Pipes, Russian Огонь, вода и… медные трубы, Ogon, 1968 fantasy directed by Alexander Rou, with Georgy Millyar as Koschei.
Beloved Beauty, Russian Краса́ ненагля́дная, 1958 stop-animated film.
Sitting on the golden porch (На златом крыльце сидели), 1986 fairy tale directed by Boris Rytsarev