Melosea is an amphibian looking alien with six limbs. His skin is mainly blue, with the exception of hands, feet, and mouth which are yellowish. He has a long, yellow tongue. There is a membrane between each of his fingers. He wears a black and green uniform.
The Omnitrix symbol is located on his chest.
- High Speed Swimming- Melosea can achieve great speeds underwater.
- Underwater Radar- Melosea is able to sense incoming objects due to enhanced hearing in water.
- Versatile Tongue- Melosea can use its elastic tongue to move around. It also secretes a neurotoxin.
- Musical Mastery- Melosea instinctively knows how to use any instrument he finds.
- Vocal Powers- Melosea can use his voice to dissociate enemies or create a powerful scream.
- Aquatic Features- Melosea is able to breathe and see underwater.
- Retractable Dorsal Fins- Melosea has dorsal fins that he can extend from his forearms, thighs, cheeks, and sides for increased defense and durability. As well as improve his ability to travel in stronger currents.
- Land Mobility- Melosea is not very mobile outside of water.
Melosea is the Omnitrix transformation of the Wasca, a race of amphibian-like aliens hailing from the luscious blue planet Teish. Unlike the oceans of Earth, there is not simply one large ocean but rather several hundred small pounds like oceans scattered throughout the planet. Each ocean is seen as its own individual nation. In each of these small oceans are several massive underwater cities in which the Wasca live their days in peace. Hunting the local aquatic life for the massive parties that they perform, which are said to be the best in the galaxy due to the amazing musical talent that these frogs possess. Wasca music is so wonderful, even a normal human can hear it clear as day even when submerged underwater, some say it sounds even better than when you hear it on land. Naturally, this talent has caused the many inhabitants of the universe to declare them some of the greatest musicians in the universe, with their many songs becoming humongous hits on the galactic extranet. During the beginning stages of their introduction into the universe however, this talent actually caused them a bit of trouble. Several Wasca civilians were kidnapped and sold to powerful alien criminals to become their personal private musicians, the kidnappers were even able to make tons of money off their powerful neurotoxin on the black market. Luckily that isn't as much of an issue anymore.
The Wasca often chant "Wasca, Wasca, oota eata ora!" whenever they're partying or simply having a good time. The chant translates as "Wasca, Wasca, we sing with joy!" it is said so often by their people many believe it to a code for which they live by.
Ben first transformed into Melosea during an escort mission of a very famous Wasca music group. Because he's rarely around a member of the species when choosing the name of a new transformation he took advantage of the situation and allowed the members of the band to pick the name. They of course decided on Melosea.
- Wasca females are much skinnier and have purple skin instead of blue.
- The original design of Melosea was created using the video game Spore.
- The natural predator of Meolsea is called a Koteail which is a massive whale like beast.
- Melosea, along with the transformations Dental Dam, Pre-Oxidized Bloodline, Backwash, Cryonyx, Crazyvulgar, Head Chef, Disk Jokey and the final form of Floof, Floofiest. All made cameo appearances in the Ink Tank's 300k Subscriber Special, What Ben 10 CAN and CAN’T Turn Into | Rules of the Omnitrix.