As Kyōya he appears as a short boy, around Kitarō's height, with black hair that reaches up to his ears, orange irises in his eyes and fair skin. He wears a green long-sleeved collared shirt with a yellow body, a pair of pale green shorts and green shoes with white tips and white socks.
When he reveals who he truly is, his body starts to morph into a more serpent-like form, having a long serpent lower body, he gains a horn with a spiral line going to the tip on his forehead, he gains broader shoulders and his arms become longer. He has light teal scales with dark teal spots arranged in spiral-like patterns, his hair becomes white, his irises turn yellow, his mouth is now filled with sharp teeth and his hands now have sharp nails. Seven salmon pink tomoe are aligned from his shoulders to his stomach.
Later his form changes again, his face is now much like an adult, with shorter hair that stands, his ears become sharper, his eyes now have black sclerae with purple irises and two black lines cross down through them. He now has a muscular build, with a dark teal pattern on his arms, the seven tomoe are now spread over his chest from shoulder to shoulder and his horn is longer with a more defined spiral pattern on it. He also now has a pair of legs, his arms ends with eyeless serpent heads and his serpent tail is now attached onto his back.
Yato-no-Kami's true body is that of a titanic sized, eight-headed serpent with a large midsection. He has pale green skin, with a scaly white stomach, while his midsection has numerous intricate red markings that reaches the hood of his main head, a row of black spikes is aligned in the middle with the back having larger spikes spread beside them, the secondary heads are attached to the sides and the edges of the skin near the underside acts like a skirt of a slug. His main head resembles a cobra with a horn on the tip of his snout, a red spherical jewel sits in a crevice between his eyes, a pair of extensions that have orange hair underneath, two rows of black spikes on his hood, between the skin, which acts like a cloak, and underside is a slate gray area that covers his mouth. His eyes are yellow with black, thin slit pupils and are sunken, with dark purple skin surrounding them, long black marks with purple spots appear on the slate gray area near the eyes. His mouth is filled with sharp white teeth and a long, red forked tongue. The seven secondary heads are all identical, they are smaller than the main head, they have pale yellow-green skin, with black crack-like markings across their necks, a white underside and three pale green plates are aligned over one another above their giant eye. Their eyes have red sclerae with black, thin slit pupils, while their mouths are filled with sharp white teeth and red forked tongues.
GeGeGe no Kitarō: Nippon Bakuretsu!!
Transformation: Once he began remembering who he is, his false body starts transforming from his Kyōka form to resemble a more serpent-like form.
Deadly Venom: Having a snake physiology, Yato-no-Kami's false body is able to inject venom to his target through biting them. The venom is said to be so deadly that it would have killed Kitarō.
Petrification Breath: Once he returns to his true body, Yato-no-Kami's others heads breathed out gases that turned organic beings, such as the birds and humans, to stone.
Yatonokami was based on the Yatonokami or Yatsunokami (夜刀神, lit. "Night Sword God"), a serpentine god appeared in the Hitachi no Kuni Fudoki.