Metashark, number 004 in the pokedex, is known as the Metal Shark pokemon. It's skin is not made of actual metal, but it is very hard and can take many hits, similar to it. They have been hunted to near extinction by fishermen and sailors, and now very few are left, none of which are in the wild.
They appear to be regular sharks, with a tough, metallic and shiny layer on their top side. This layer of armor extends all the way from the tip of it's sleek tail, to over it's face, giving it a "spike" sticking out over the eyes and face. Scientists think this is there to act as protection when ramming into preditors/prey. They can weigh up to 100 pounds, surprisingly light for such heavy armored skin. On average one is 6-10 feet long.
In the wild they ate fish, and occasionally, other Metasharks, if low on food supply, or in a fight. They usually swim alone, or in pairs, relying mainly on themselves for everything. Once born, they immediatly must hunt for themselves, for the mother will accidentally eat them if they stay too close.
They used to live in warm, shallow seas, away from larger preditors, but close to small, edible fish, mainly Fuguto and Frillery. Unfortunatly, shallow waters are an ideal hunting ground for humans, since it was so simple just to ride a boat by and swing a single net, catching tons in a day.