When it came to Gastrodon, many people might not be very familiar with it.
Gastrodon's appearance might have been based on nudibranchs, and it also bore some resemblance to slugs, generally with rather vivid coloring.
It had hornlike feelers and an eye-like pattern on its forehead that made it look as though it had three eyes. It had no bones, and its body was soft and floppy. Differences in seawater composition had also given rise to its West Sea and East Sea forms, which differed in color and appearance, though their abilities were the same.
In terms of classification, Gastrodon was related to Shellder and Cloyster. It lived in coastal shallows and was abundant along rocky shores with gentle waves. It was more active on overcast and rainy days than on sunny ones. Its soft body helped disperse the impacts it received, and it fed on sand from the sea.
It was said that in the distant past, Gastrodon's entire back had been covered in a hard shell that protected its body. Even now, traces of a thin, hard shell remained inside its back. Slippery fluid covered its entire body, and it left sticky slime wherever it went. When attacked by natural predators, it released purple liquid from its body to escape. Although the fluid was not poisonous, it was very difficult to clean off once it stuck to something. Its regenerative abilities were also exceptional-even if a fish Pokémon bit off part of its body, it would recover within a few hours.
As a Pokémon that only began appearing in Sinnoh, Gastrodon was something Xia You had rarely seen in battle. By contrast, he had seen plenty of Magcargo, its opposite, which made him rather interested in seeing just how this Pokémon fought.
Facing this Pokémon, Ash did not