Parallax

Parallax is a shoot 'em up video game developed by British company Sensible Software for the Commodore 64. It was released in 1986 by Ocean Software in Europe and Mindscape in North America. The game was named after its primary graphical feature, parallax scrolling, which gives the illusion of depth to side-scrolling video games. On release, reviews praised the game's mix of traditional side-scrolling action and adventure game-inspired puzzles. (wikipedia.org)