10x, A.K.A. Experiment 266, is an illegal genetic experiment created by Jumba Jookiba. He is designed to multiply himself by 10. His one true place is back in Jumba's possession to remain in storage until he warrants being used again.
Experiment 266 was the 266th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to multply himself by 10 so he can cause 10 times as much trouble.
266 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
All of the experiment pods were released and scattered across the island of Kauai.
At an unknown point, he was activated, captured and named 10x.
10x was not malicious so he didn't need neutralization. However, after Stitch ignores Jumba's warnings and wears 10x too long, Lilo saves Stitch from near death by pulling 10x off of him.
The first 624 experiments, including 10x, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben and Gantu arrived before the experiments could be destroyed.
It is unknown whether or not 10x participated in the following battle between the experiments and the Leroy clones.
The Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song Aloha Oe, which caused the Leroy army to shut down due to the original Leroy's failsafe.
10x is a pink and yellow dragon-like experiment.
He can multiply himself by 10 so that it can cause 10 times as much trouble. He can also crawl around on his four legs.