Historically, I don't see how it can be any game other than Super Mario Bros. That game releasing with the NES established Nintendo and Mario as household names. The original Super Mario Bros. over-world theme is arguably the most iconic tune in gaming history and one of the most iconic sounds in pop culture. Anybody, anywhere, who hears it, knows right away what it is. But even more importantly, it revived the video game industry and brought it back from the brink it was in after the crash of '83, and the industry hasn't looked back since. Greatness in terms of the game itself and how great it is or plays is purely subjective, same with every other game on this list, But in terms of its importance to the video game industry, the console it launched on, the company that developed it, and its impact on pop culture... It's no contest. Let me put it this way, there would be no Breath of the Wild, if there was no Super Mario Bros.
There's Super Mario Bros., and then there's everything else.
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