Sinker

Sinker, A.K.A. Experiment 602, is an illegal genetic experiment created by Jumba Jookiba. He is designed to slice sea vessels in half with his massive dorsal fin. His one true place is cutting up vegetables and fish fillets at a Japanese restaurant.

Bio
Experiment 602 was the 602nd genetic experiment created by Jumba with Hämsterviel's funding. He was designed to slice enemy sea vessels in two with his massive, razor dorsal fin.

602 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 602 was activated.

Lilo & Stitch: The Series
When Keoni was practicing for a boat race, 602 sunk his boat while Lilo and Stitch were watching.

Later, when Lilo and Stitch attempted to capture 602, the latter proceeded to sink their boat as well. When Jumba and Pleakley tried to go rescue them, 602 sunk their raft also.

602, named Sinker, then proceeded to sink Gantu and Experiment 625 numerous times when they attempted to catch the former, and presumably sunk other boats.

Later, Lilo, Stitch, Jumba and Pleakley stowed away on a large cruise ship and tried to figure out how they would capture Sinker, slippery as he was. Eventually, Jumba came up with a plan.

Wearing scuba gear, Stitch dove underwater and tried to find Sinker, but the latter hid in a cave until he eventually came out, revealing the small size of his body. Sinker then escaped and tried to sink the cruise ship. However, Stitch managed to capture Sinker in the ship's anchor and chain.

Shortly after, Sinker found a one true place at the sushi restaurant, cutting up fish fillets and vegetables.

In "Ploot," Lilo tried to convince Sinker to help her defeat Ploot, but he was unable to because he was really busy cutting up food for a large party while the other chef that worked there was sick.

Leroy & Stitch
The first 624 experiments, including Sinker, were round 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 Sinker participated in the following battle between the experiments and the Leroys.

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.

Stitch! anime
Sinker made an appearance in the Stitch! anime where Hämsterviel used him along with Slushy to attack a cruise ship that he had lured Stitch onto. It is also revealed that Sinker has a blind spot on his dorsal fin and he will become immobile if forced into a horizontal position because of his large fin.

Personality
Sinker is shown to be greatly offended by the mocking of his size compared to the rest of him. He is also incredibly territorial and will claim an entire area of water, sinking any sea vessel that sails in that area.