I need help finding an early 90's anime

[stupidkupid1]

I've been trying to find this anime from the early 90's I believe that has a man that can turn into a hydra....a fire breathing hydra or dragon(pretty sure when he transforms he has multiple heads) I think. I know he serves this evil sorcerer guy or something. I would classify it as a medieval fantasy supernatural type anime. I'm pretty sure it has ogres/demons in it to. I also remember a young boy who has to fight those kind of creatures. Can't remember much more than that so can anybody help me find the name of this please!

[stupidkupid1]

Bump.....

[Dengaku]

Could you perhaps be thinking of "Giant Robo"? I remember that anime, and I believe it fits what you remember.