He is the first experiment created before Dr. Jumba started assigning numbers to the other experiments. Jumba created this ultimate killer monster, but the result was more than he could handle. He couldn't control experiment 000 until he finally suspended him and locked him away on an icy planet. Experiment 000 escaped and acquired mechanical body parts, making him so powerful that not even Stitch could stop him. He was eventually defeated and captured.
Experiment 000 was originally a purple version of Stitch. He now turned into a black, cyborg experiment, part machine part alien. His form resembles a cross between some sort of lizard, and koala (and robot). He has a two cyborg arms, three spider-like legs, and half-helmet with a cyclonic-like right eye from some unknown incident. His cyborg arms serve many purposes such as cybernetic wiry rope, laser guns, a forked harpoon and welding tool, and his cyborg eye has zoom functions and improves his aim. In cyborg form, he is missing his nose.
In his original form, experiment 000 has all the powers of Stitch. In his cyborg form, he repairs android minions, spaceships and a doomsday device (super nova warhead).