Greendog: The Beached Surfer Dude! is the title of a side-scrolling platform video game developed by Sega Technical Institute and Interactive Designs for the Mega Drive/Genesis home console, and was published by Sega of America in 1992. A ported version for the handheld Sega Game Gear was released a year later.
The eponymous protagonist of the story is "Greendog", the player character, a laid back, cool surfer and skater with a mop of bleached blonde hair. He has surfed most of the biggest waves around, including off the coast of Australia, California and in the Mediterranean, and is always in search of the biggest waves which will give him the biggest thrill and he cares for little else in life. He has numerous contraptions and toys, such as a gyrocopter, inline skates, a skateboard and an antique frisbee which could be very dangerous in the wrong hands. He doesn't say much except "dude" and "cool".
One day, while surfing in the Caribbean Sea off the coast of the Grenada islands, Greendog is knocked off his surf board by the biggest freak wave he has ever seen, and falls unconscious in the sea. When he wakes on the beach, he is apparently in another version of our world, or at least some form of very vivid dreamworld, and a mysterious and apparently magical golden pendant is tied around his neck and he is unable to remove it. A beautiful, buxom blonde woman in a red bikini appears and explains to Greendog that the pendant is of Aztec origin and carries a terrible curse; it dooms the wearer to be attacked by animals and wild primeval creatures and, worst of all, will prohibit surfing.
The only way that Greendog can lift the curse is to travel to a lost Aztec civilization and track down six pieces of a sacred Aztec treasure which were scattered across the Caribbean Islands, so that the pieces can be put back together, and ultimately so that Greendog can remove both the curse and the pendant. However, nobody knows exactly where the pieces of the treasure are.
Source: Wikipedia, "Greendog", available under the CC-BY-SA License.