Oh-So-Snake

The Oh-So-Snake is the boss of Chapter 2 in Mother 3. It is fought in the water channels below Osohe Castle by Duster, Kumatora and Wess after they retrieve the Egg of Light from the castle's top. Its most devastating attack is creating a powerful wave.

Battle Memory description
"An enormous snake that rules the Osohe Castle basement. Disturb its sleep and it will tidal wave you goodbye."

Trivia

 * Oh-So-Snake's Japanese name is a pun on オソヘ Osohe, and ヘビ hebi, meaning "snake".