Kaa, also known as Zit and Patch, was a huge mutie with powerful psionic abilities. He had a pineal (third eye), which he had to open and close manually. When open, it enabled him to use his powers to communicate and control muties, most notably stickies. He started out life in Baron Willie Elijah's mutie zoo, but gradually wormed his way into the baron's good graces and gained access to the library, where he learned all sorts of things, including how to work the gateways.
He escaped from Willie ville and used his powers and knowledge to gather and control a huge stickie army, with which he planned to wipe out all norms in Deathlands. The companions stumbled onto his plan, however, and warned the ville ahead of time; his army was largely wiped out, and Kaa himself fled to the nearby redoubt, where he used the gate to jump to a new location. The companions followed with a small nuke, which they set on a timer and jumped back to the first redoubt; Kaa activated the gate a millisecond before the nuke went off, and he was lost in the system. (Skydark novel|Skydark)