Dupe

Dupe, A.K.A. Experiment 344, is an illegal genetic experiment created by Jumba Jookiba. He is designed to clone individuals into multiple replicas, though the individuals' traits are divided between their clones and originals. It is possible for Dupe to reverse the cloning. His one true place is making half-calorie Shave Ice cones with Slushy.

Personality
Dupe is a fun-loving, childish and immature experiment, due to the fact he was programmed to be one of the younger experiments (along with Mr. Stenchy and Babyfier). Because of this, he is often treated as the baby of the heroes' side, rarely fighting. His main purpose is to serve as a cloner to make other soldiers, and to heal wounded soldiers. He is very playful, friendly and optimistic, often trying to cheer up his fellow comrades in the worst of times.

Lilo & Stitch: The Series
Experiment 344 was the 344th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to use his clone-generating ability to clone single individuals into entire armies, but all of the original's traits were divided between them and the clones. 344 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 after this, Experiment 344 was activated.

An estimated 12 hours after his activation, 344 was captured by Lilo and Stitch and taken back to the house, but not before being pursued by a relentless Gantu.

After Jumba explained 344's powers, the latter demonstrated them by first duplicating a lollipop and then a huge birthday cake.

The following night, Lilo used 344, christened Dupe, to generate clones of herself that she could befriend when Mertle and the hula girls didn't show up for Lilo's slumber party that she hosted earlier. However, Stitch hastily intervened, resulting in him being cloned into four instead.

Later that night, Gantu, 609, 544, 617 and 033 attacked the Pelekai household. The Stitch clones tried to fight back, but as their strength was divided among them, they had all become very weak, thus allowing Gantu and his henchmen experiments to easily defeat and capture all four Stitches in containment orbs.

Shortly after Jumba advised Lilo her objective, she hatched a plan and used Dupe to generate three clones of Pleakley, leaving the original comatose. Lilo and the Pleakley clones then launched a rescue mission on Gantu's ship, taking Dupe with them so he could re-merge the Stitch clones.

When Gantu noticed them and learned of Dupe's cloning powers, he grabbed Dupe and cloned Heat, Thresher, Plasmoid and Hammerface each into a hundred replicas. However, as a result of being tricked by Lilo, the experiments all became complete weaklings, and thus were easily defeated by Lilo and the Pleakleys.

Lilo then used Dupe to re-merge the freed Stitch clones into the original, and Lilo, Stitch, Dupe and the Pleakley clones escaped the ship.

Dupe then re-merged the Pleakley clones into the original, and was later found a one true place making half-calorie Shave Ice.

In "Remmy", Dupe was one of the experiments in Lilo's dream.

In "Snafu", Slushy and Dupe were seen using their combined powers to sell multiple Shave Ice cones. Gantu then attempted to revert them both to evil by playing a recording of Angel's song, but due to interference from Experiment 120, Gantu's karaoke tape was played instead, much to Slushy and Dupe's humor.

Leroy & Stitch
The first 624 experiments, including Dupe, 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.

Dupe 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 fail-safe.

Stitch! anime
Dupe made an appearance in the Stitch! anime where his tweak was altered by Hämsterviel, so instead of making things weaker once duplicated, the duplicates are made stronger than the original, rather than the other way around.

Trivia

 * Dupe's pod color is yellow.
 * Dupe is described by the experiment computer screen as, "Experiment 344. Primary function: Duplication."
 * Dupe's antenna and ears appear in the online game Jumba's Lab.
 * Dupe appears in the online game Lilo & Stitch: Alien Interception along with Plasmoid, Tank, Clyde, Yang and Hämsterviel.