Need Help with movie title.

by Brad

Im hoping you can help me out. I caught the tail end of a older kung fu movie that blew me away. The end fight was set in a deserted town. The villian turned into a frog as part of his fighting style. The fight lasted like 15 minutes and was awsome! Iv seen a few kung fu flix and this end fight was the best iv ever seen. Im wondering if you know what movie im talking about and if so, can you tell me the name of it! Thanks for your time! Brad