As spider-based Badniks, Kumo-Kumos have a dark blue and round torso with a black underbelly and six long legs with spring attachments at their flat feet. The Kumo-Kumos' head consists of a black face with a violet forehead covering, a pair of black eyes and yellow mandibles. On the Kumo-Kumos' rear is a small cannon to shoot webs.
In Sonic the Hedgehog CD, Kumo-Kumos are only found at Quartz Quadrant where they either appear individually or in pairs in idle positions until the player appears. These enemies does not move along the ground, but leap high into the air. As they leap, they fire a web of sticky gunk onto the ground: run into it and the playable character becomes drastically slower for a few seconds.
In the Bad Future or sometimes in the present timeframe of the Rounds, Kumo-Kumos show signs of wear, their bodies having developed several cracks. These types of Kumo-Kumos do not leap as high and cannot shoot webs. Like every Badnik in the game, they are powered by Little Planet flower seeds which will pop out of them after being defeated.