The original US release of Metroid for the NES maintained the core gameplay and story of the Japanese release, with minor differences potentially in the text and possibly minor graphical changes to suit the regional market. It's considered to be the launch of the Metroid series in the United States, solidifying the game's impact and popularity in the western gaming market. Developed by Nintendo R&D1, it retained its groundbreaking, nonlinear gameplay design. The success of the US release was crucial to launching the Metroid franchise into widespread recognition.

Metroid (USA)

Metroid (Japan) (Rev 3)