I am looking for a cartoon movie that's a story of two crystals which makes a voice 1000 times more powerful and that's worn by two old persons. One is good, but the other one is trying to steal the remaining crystal and use its power to rule the world.
The good old person has a kid who tries to become like the old man as he tries to knockdown crows by his own voice. At last, the good old man dies by the bad guy. Before dying he makes a hammer which has the power of the crystal that he wore. Then the final battles begin between the kid and bad guy.