Gin no Mugibatake

The "Golden Wizard" is the hero who saved a kingdom, and the "Silver Wizard" is the wicked mage who killed the king.
One day, May, a baker's daughter living in the country where the legend of the two wizards was born, finds a grain of wheat in shining silver on the outskirts of town. What awaits her is a "silver wheat field" covered in shimmering stalks of silver wheat. This is a silvery fantasy woven by wizards.

(Source: GFantasy, translated)