Ecco the Dolphin (also known as Ecco) is an aquatic side-scrolling action-adventure game developed by Novotrade and published by Sega for the Genesis in Europe (on July 31, 1992), North America (on December 29, 1992), and Japan (on July 30, 1993).
Players control a bottlenose dolphin named Ecco (unique to other dolphins for the six star markings on his forehead) as he embarks on a journey through the oceans, trying to figure out the whereabouts of his group (who were sucked up in a mysterious waterspout) while helping fellow dolphins along the way.
Along with its unconventional gameplay mechanics (including a dedicated "sing" button for interaction and echolocation), the game is known for its extreme level of difficulty (which would be a staple for the main games of the series) and bizarre plot development (including time travel and alien abductions). It would later spawn a sequel (Ecco: The Tides of Time), a kid-friendly spin-off (Ecco Jr.), and a 3D reboot (Ecco the Dolphin: Defender of the Future).
Along with downscaled ports to the Sega Master System and Game Gear, the game was ported to the Sega CD less than a year later. This version (known in Japan as Ecco the Dolphin CD) features a bonus set of levels and new soundtrack (using Redbook audio), and was later ported to the PC in Japan and North America (both in 1996, featuring new high-resolution sprites). The original game was digitally re-released for the Wii (via Virtual Console on November 27, 2006), Xbox 360 (via Xbox Live Arcade on August 15, 2007), PC (via Steam on June 1, 2010), and most iOS devices (on July 22, 2010), and was included in two compilations: Sega Genesis Collection (for the PlayStation 2 and PlayStation Portable), and Sonic's Ultimate Genesis Collection (for the Xbox 360 and PlayStation 3).
An enhanced port was made for the Nintendo 3DS (as 3D Ecco the Dolphin, part of Sega's 3D Classics remake series) and digitally released on the 3DS eShop on December 12, 2013 (June 26, 2013 in Japan). This version features stereoscopic 3D and a significantly-easier difficulty setting (adding invulnerability and unlimited air).