"Dewgong loves to snooze on bitterly cold ice. The sight of this Pokémon sleeping on a glacier was mistakenly thought to be a mermaid by a mariner long ago."
Another case of art imitating life, Dewgong is not only named after an actual animale, it resembles it greatly. In fact, Dewgong were said to save sailors from shipwrecks, and became the basis of the mermaid legends because they would have seaweed stuck on their heads, thus making them look more human like. While Dewgong doesn't have that, it does have plenty of power if raised right.
Dewgong's Basic Attacks are Frost Breath and Ice Shard. While its Special Attacks are, Icy Wind, Aqua Jet, Aqua Tail, and Blizzard.