The key features to the sword was that it changes color multiple times in a day, and it represented joyousness. More of a mass media weapon than a slaying device.
For the color feature, I settled on using opal as a material source. Opal was reputed to be a gemstone that changes color, even when the owner dies. The change of light throughout the day would change the refracted light from the sword, so it explains the color-changing feature. Continue reading