Contra is a run-and-gun style platformer developed by Konami and published by Erbe Software initially in 1987. It was released in arcades and on ZX Spectrum and Amstrad PC to start with. The NES version was released in 1988 and several changes were made to make it more compatible with NES hardware.
A few notable changes are that the year it took place was changed to 1987 and the setting was changed to the Amazon. The two main characters also got badass code names, Mad Dog and Scorpion. 