Salamander , retitled Life Force in North America and in the Japanese arcade re-release, is a scrolling shooter arcade video game developed and published by Konami. Released in 1986 as a spin-off of Gradius, Salamander introduced a simplified power-up system, two-player cooperative gameplay and both horizontally and vertically scrolling stages. Some of these later became normal for future Gradius games. In Japanese, the title is written using ateji, which are kanji used for spelling foreign words that has been supplanted in everyday use by katakana. Contra, another game by Konami was also given this treatment, with its title written in Japanese as 魂斗羅 .

Konami Group Corporation , commonly known as Konami, is a Japanese multinational entertainment company and video game developer and publisher headquartered in Chūō, Tokyo. The company also produces and distributes trading cards, anime, tokusatsu, pachinko machines, slot machines, and arcade cabinets. It has casinos around the world and operates health and physical fitness clubs across Japan.