Kojima was asked to take over a project, "Metal Gear", from a senior associate. Hardware limitations hindered the development of the game's combat, and Kojima altered the gameplay to focus on a prisoner escaping instead of fighting, inspired by "The Great Escape". It was released on July 13, 1987, for the MSX2 home computer in Japan, and on September in that year for Europe. The player controls a special forces operative codenamed Solid Snake, who is sent to the fortified state of Outer Heaven to stop a nuclear-equipped walking tank known as "Metal Gear". "Metal Gear" is one of the earliest examples of the stealth game genre. A port of "Metal Gear" was released for the NES in 1987, with altered graphics, difficulty, and an abridged ending without the titular weapon. Kojima has openly criticized many of the changes made in the port, including poor translation and the abridged ending. In an interview, a programmer on the NES version of the game said his team were asked to complete the port in only three months, and the NES hardware was not capable of implementing the Metal Gear fight.