Ryan was trying to scare the public tourists away from the beach by using his and his friend's Medabots to look like a giant Sea Monster. He did this because his father felt that tourists polluted the ocean and had no respect for it. Ryan specializes in combat at sea and his Medabot partner is Sharkkan (who partook in the Sea Monster plot). They defeated Metabee because he wasn't able to battle in the water and loses his legs to them.
Following the exposure of Ryan's plot, Metabee fought Sharkkhan again in a rematch with his new Tentaclam legs. With some wisdom from an old man about how a shark strikes, Metabee was able to defeat Sharkkhan and win his legs back from Ryan.