Game: In Search of Dr. Riptide

Dr. Riptide is hell-bent on turning all of the world's marine life into high-protein slurry, and must be stopped. Nick must navigate his way through both natural caves and man-carved tunnels. These take him from a beach, deep into a reef, back to the surface, and then deeper into a reef. Along the way, he encounters 2 giant marine life-based monsters, Oscar the giant bionic fish and Otis the giant octopus. He also makes his way through chambers and ruins of a Greco-Roman Lost City of Atlantis. His enemies are mostly evil aquatic animals life, typically capable of throwing fire balls: piranhas, crabs, sea horses, tulips, octopus arms, and sharks. All the while, Nick must salvage for oxygen, ammunitions, weapons, and collect gold coins. Eventually Nick makes his way to the metal-encased laboratories of Dr. Riptide, which are deep underwater, under many feet of coral. There he battles the nafarious Doctor, who pilots a large, weapon-equipt submarine. Nick defeats Dr. Riptide, Riptide's submarine breaks down, and Nick tows him away to the authorities.
Each game uses different controls, most DOS games use the keyboard arrows. Some will use the mouse , "Alt" ,"Enter" and "Space bar".