Shimo is depicted as a reptilian monster with some similarities to Godzilla's evolved form. A quadrupedal creature with white scales, she possesses Stegosaurus-like thagomizers on the tip of her tail and crystalline spines down her back, both of which are a blue color. The spines cover her entire back and thin into a line of spines going down the length of her tail. Shimo is also adorned with many crystals arranged in a crown-like formation protruding at a horizontal angle from the back of her head. A continous row of sharp scutes located on her sides run from where the back of her head connects to her neck to the thagomizers on her tail. Despite her large size, Shimo's abdomen and legs are very slim. Her eyes appear to be blue with black pupils, though her pupils are obscured when she glows bright blue. While Shimo assumes a bear-like stance when quadrupedal, merchandise reveals a silhouette of the creature taking on a fully upright posture.