Into the Veil of Mists
In the Comic, "Dangers of the Deep", fishermen are turning up with little to no fish for the Hairy Hooligan Tribe to eat. Chief Stoick decides to take all able-bodied tribesmen out to sea into the Veil of Mists in search of fish. Thick fog surrounds the Hooligan ships as they enter and the sailors can see something stalking them in the water. Stoick instructs "Gust - signal the other ships. Oars in and get going." The creature stalking them turns out to be a Submaripper.
It is not clear from the image in the comic if the background Viking is Gust, or another Hooligan. If so, Gust is a sturdy adult male with a developed upper body. He also has brown hair and a thick brown moustache, but no beard.