Mohmoo

First Appearance: Chapter 73 Episode 31 Mohmoo is a giant sea cow literally that was brought from the Grand Line by Arlongs crew. It was he that destroyed Gosa Village. However when he encounters Luffy Sanji and Yosakus boat he is promptly beaten and used to tow their boat to the island. Later during the battle at Arlong Park he called upon by Hatchan his caregiver to the fight the Straw Hats. Despite memories of his first defeat he does as told only to be used in the Gomu Gomu no Kazaguruma an attack by Luffy that takes out most of Arlongs forces and then was thrown out of Arlong Park in the process never to be seen again. Momoo is possibly an ophitauros. It can make a moooing sound like any cow. Apparently it got no problem staying on land since Arlongs crew pulled it right through the Gosa Village without it getting any known damages. Source: One Piece Wikia