S.Peelman on 03 May 2013
Metroid fell off it's pedestal, true (if it was ever on one in the first place), but it's still part of the 'Big Three' mainly because of tradition. Those three were the first. Sure Donkey Kong is even older, and Mario is 'just' a spinoff to it, but DK was almost non-existant in the NES age.
(Super) Mario (Bros.), Zelda and Metroid were first released in a short time-span at the start of the NES's life. The first wave if you will. The three were Nintendo's different 'paths' of gameplay. Mario the skillful linear platform game, Zelda the puzzle-solving adventure game, Metroid the fast-paced action game. They are vastly different in their foundation, which made them unique and their character's iconic.
