Seanister

Seanister is a Water/Dark Fakemon made by Darksilvania. It evolves from Riveathan and into Atrocean.

Remade Version
Seanister is a Water/Dark Fakemon made by Darksilvania. It evolves from Marigne and into Atrocean.

More info
Species: Black Lagoon Pokémon Pokédex: "Their bodies are colored to match the coloration of the swampy water, so they can move under it withouth being detected. Now their back fins has evolved into fully developed legs, which allows them to walk freely on land, but their posture makes them look strange when doing so. They are known as the 'Swamp Monsters'."