Really, the main reason MG is a great series
Don't get me wrong, the first MG is a great story too, but the story in MG2:SS is what catapulted it into such a complex series. It had the most 3-dimensional characters that a game had ever had. From building upon that, the MGS titles would be the best in storytelling. Sure, some things got retconned like Big Boss being Snake's father and the patriot story period (but Kojima is a mad genius, and he pulled it off) but the complexities of MGS and its sequels have this game to thank.
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