Ecco the Dolphin is an action-adventure game originally developed by Ed Annunziata and Novotrade International for the Mega Drive/Genesis and published by Sega in 1992. Ecco the Dolphin was republished digitally via Nintendo's Virtual Console in 2006, Microsoft's Xbox Live Arcade, Steam, iOS, Nintendo 3DS, and Nintendo Switch Online + Expansion Pack. It is the first installment in the Ecco the Dolphin video game franchise. The player character is a bottlenose dolphin who travels through time to combat hostile extraterrestrials in Earth's oceans and on an alien spacecraft. Gameplay Ecco can attack enemies by ramming into them at high speeds. Swimming can be made progressively faster by tapping a certain button, and the speed can be maintained by holding it down. Players can perform a purely aesthetic spin in the air when jumping out of the water. Two features of the gameplay are based on actual dolphin habits: one button causes Ecco to sing, allowing him to speak with other cetaceans and interact with certain objects. The same button is used for echolocation: holding it down causes the song to return, generating a map of the area. Several levels contain enormous crystals called glyphs, which respond in different ways if Ecco touches or sings to them. Some block paths, and a "key-glyph" must be found in such cases to pass. Others give information, and a few in later levels replenish health/air and give Ecco temporary invulnerability. Additionally, Ecco, being a mammal, must surface periodically for air, or else find an air vent. If the "air meter" runs out, Ecco loses health rapidly, which represents drowning. His health is measured by a separate meter (above the air meter); it is depleted by enemies or when his air meter runs out, and it is recharged by eating fish, "singing" to clams, or, later in the game, singing to special statues or glyphs. Ecco's song can be optionally upgraded at two points in the game: one upgrade allows Ecco's song to be used in combination with a charge as a long-range weapon, and the other temporarily disorients sharks and makes minor enemies freeze temporarily. Touching any enemy by any means other than an attack causes Ecco to sustain damage. The enemies range from seahorses to giant octopods. Plot The game opens with Ecco, a bottlenose dolphin, as he and his pod are swimming in their home bay. A podmate challenges Ecco to a