Super Smash Bros. Ultimate director Masahiro Sakurai wrote about the game this week in Famitsu, talking about World of Light's inspiration, how the series has transcended its "Nintendo All-Stars" moniker, and more.
Regarding the series' "Nintendo All-Stars" moniker: Sakurai believes that the series has evolved beyond that. In his definition, Sakurai believes the series is defined by its gameplay, and that it being just another 1v1 fighting game would make it no longer Smash.
Between this remark, as well as Reggie's insistence that the Joker DLC is indicative of the strategy Nintendo will be following with the Smash Fighters Pass, it's pretty clear Nintendo is now looking to expand the inclusion of third party characters in Smash. I guess Super Smash Bros. Melee was the last time that Smash would be "Nintendo's All Stars".
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