The Origin of Stitch is an animated short included on the DVD release of Lilo & Stitch 2: Stitch Has a Glitch and later added to Disney+ as an extra to the same feature film. The short has a total running time of 4:35 minutes and serves as a bridge between Stitch Has a Glitch and Stitch! The Movie (as well as Lilo & Stitch: The Series). In the short, Stitch discovers Jumba's secret computer that reveals what creatures Jumba had used to create Stitch and also hints at his other 625 experiments. Stitch is scared to find out what a monster he is, only for Jumba to come and explain how he found love when he met Lilo. The short was directed by Mike Disa and co-directed by Tony Bancroft.
The following creatures are mentioned to have had some of their DNA incorporated into Stitch:
Fearsome Manglyoid of Upmoridian Four: Same claws
Goo-Gobbling Booger-Beast: Same habit of picking nose with tongue
People-Eating Puss Monkey: Same eyes
Deadly Disemboweler
Boiling Tongue-Boid
Bottom Feeding Scum Sucker
Although it is spoken as a denial of his old name, this is the first time that Stitch speaks his own experiment number, 626.
If viewers can see closely while Jumba is explaining to Stitch that his cousins can cause destruction, on the bottom left corner, there is a screen gliding through most of the experiments that have appeared in the series.
For the most part, the experiments are going backwards in this short, and nine of them have different numbers for unknown purposes. Most viewers thought they were going in an incorrect order, but they actually have different numbers, because Fudgy is 119 and Mary is 086.
If Stopgo were to be on the screen, he would possibly be 239.
627 is seen in the lineup, but he does not exist until Jumba created him in one episode of Lilo & Stitch: The Series.
If viewers can look closely in Stitch's eyes when the experiments are gliding, Drowsy is shown not yawning, Heckler is gagged and handcuffed, and Shortstuff is looking directly at the screen instead of to his right.
Precious was originally going to be one of the experiments that was gliding on the screen, but due to the copyright issues, she did not appear.
Most of the experiments that appear have the wrong numbers.