The Sega Genesis and SNES versions vary somewhat. Although the missions are the same, the graphics are significantly improved in the SNES version, as well as the difficulty reduced. In the Sega version the firing of the ships is faster as well as the pace of rest of the gameplay. Additionally, the method of firing and aiming missiles changed: the Genesis version required the missile to dive on a target while in the SNES version the missiles oscillated from side to side. In addition, the SNES version also has Taps play whenever a ship sinks.

Wikipedia
http://en.wikipedia.org/wiki/Super_Battleship