Metroid is a 2D shooter for the NES, and is a single player experience. It was published by Nintendo.
Metroid is a commonly available game for the NES. It shouldn't be too difficult to find this game for purchase. In good condition, the game is worth about $17.00. Metroid was released in August 1986. The save feature for Metroid is: Password.
To get every thing, type JUSTIN BAILEY (and fill the rest in with dashes). Well, almost everything - you won't have the Ice Beam.
Type the following password in at the password screen:
00WX00 2W0000
41TW1o 0000lD
Please note that the letter next to the D is a lower-case L.