Anyone recognize this anime movie from the mid '80s?

[basicflytrap]

I have a pretty random question. I don't know much about anime, which is why this is my first post on the forum. I have a rather strange question. I'm hoping someone can identify the movie. I only vaguely remember a few scenes, but even though over 20 years have passed, I've always been intrigued by it, and would like to see the whole movie. Here is what I remember:

There was an evil wizard of some kind, that was turning people into green zombie type creatures, and the creatures were all stacked into a big wall. The zombies all looked identical to each other after being transformed. I remember a scene where a couple children had their parents turned into the zombie creatures. I also vaguely remember a guy sitting on a log or something and playing a flute. If I remember right, the flute playing had some significance. I think he was a good guy but I'm not sure. I remember the movie seeming very scary to a young child.

I'm sorry it that seems very vague. I'm not sure when exactly the movie came out, but I couldn't been older than 7 or 8 when I saw a few scenes from it, meaning it was out by 1987.

[LeRolls]

Damn, wish I knew the name of your anime. I know what it's like to have images stuck in your head from when you were a kid and not knowing where they come from. I had to deal with the same thing but at least I was finally able to figure out that my movie was called Windaria which ADV changed the title to Once Upon a Time when they released it on DVD.

[zerog]

Grave of the Fireflies maybe?