Hideo Kojima's "Metal Gear", released in 1987 for the MSX2 and the Nintendo Entertainment System in 1988, utilized stealth elements within an action-adventure framework, and was the first mainstream stealth game to be released on consoles. Since the MSX2 was not available in North America, only the NES version was released there. "Metal Gear" placed a greater emphasis on stealth than other games of its time, with the player character Solid Snake beginning without any weapons (requiring him to avoid confrontation until weapons are found) and having limited ammunition for each weapon. Enemies are able to see Snake from a distance (using a line-of-sight mechanic) and hear gunshots from non-silenced weapons; security cameras and sensors are placed at various locations, and a security alarm sounds whenever Snake is spotted and causes all enemies on screen to chase him. Snake could also disguise himself in enemy uniform or a cardboard box, and use his fists to fight enemies.