Wonder Dog is a side-scrolling video game developed by Core Design and released by JVC for the Sega CD in 1992. It is one of the first games developed for the system. In the game, players control a dog who must rescue his home planet from invading forces.
The peaceful dog-ruled planet K-9 finds itself under attack by the evil Pit Bully empire. In a last-ditch effort to save his world, Dr. Kibble fast tracks the Wonder Dog project, an experiment to create a superpowered dog. Running out of time, he tests the serum on his newborn son and sends him to Earth with a special outfit called the Wonder Suit. His son crash lands on the planet and immediately befriends a boy. However, the two are separated as the boy's father won't let him keep the dog. The dog then returns to the ship, dons the Wonder Suit and becomes Wonder Dog, who must save the planet K-9 from the Pit Bully invasion.
Source: Wikipedia, "[en.wikipedia.org/wiki/Wonder_Dog_%28video_game%29 Wonder Dog (video game)]", available under the CC-BY-SA License.