The Hyakki Gokai is a hyper-stylized, ornate weapon with a curved, asymmetrical blade that glows with a vibrant, luminous energy. Its surface features intricate engravings of mythical creatures, and the blade transitions from a dark metallic base near the hilt to a translucent, glowing tip. The hilt is wrapped in patterned leather, providing both grip and aesthetic appeal, with a small, iridescent gem embedded at the pommel.