[TheGame]

Metal Gear (1) had a very basic storyline, one that could be told in less than a paragraph maybe. lol

MSX2 (Metal Gear 2) is where you finally get a somewhat deep story.. It doesn't compare to MGS games in deepness, but it was the first with its theme of blurring the lines between good and evil in war is is definently a relevant story to help push along the newer ones.

I would say MSX2 is more needed to understand MGS1 then MGS1 was needed to understand MGS2. Raiden was a new fresh character who dismissed his whole past, so you don't need a game before to understand him. And he's thrown into a wild situation that was escalating for years that he knows nothing about so its a bit easier to relate to Raiden then the veteren Snake.

In MGS1 Snake has already long known the Colonel, Big Boss, and Grey Fox, and their stories were very relevant to the game, and snake was already a legendary mercenary but for reasons you never got to play through if you start with MGS1.