Metroid II: Return of Samus is an action-adventure game developed by Nintendo R&D1 and published by Nintendo for the Game Boy in November 1991. The second main entry in the Metroid series sends bounty hunter Samus Aran to the caverns of the planet SR388, where she must exterminate the remaining Metroids in their various evolving forms. As she clears each region, the planet’s acid level drops and new depths open, drawing her closer to the Metroid Queen.

Built for a small monochrome screen, the game is remembered for expanding the series’ exploration into a larger, more labyrinthine world, and for giving Samus a spider ball, space jump and other abilities that redefined how she moved through it.