The trailer for Nintendo's newly announced Paper Mario: The Origami King concludes with a reference to the Super Metroid series. It's an odd joke to include in a trailer for a Paper Mario game, but this seemingly random gag could instead be a tease for a new Metroid title, based on previous rumors and leaks that may have proven true.

Following rumors that there would be no June Nintendo Direct, Nintendo's relatively bare 2020 Switch lineup was looking increasingly concerning. Besides Clubhouse Games: 51 Worldwide ClassicsBravely Default 2, and No More Heroes 3, little more than a few DLC packs for existing Switch-exclusive games had 2020 releases planned. Then Nintendo dropped a surprise announcement trailer for Paper Mario: The Origami King, set to launch this summer.

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The Origami King's reveal comes after a period of uncertainty for the Paper Mario franchise. Its latest game, Paper Mario: Color Splash, received middling reviews, and the series has since been silent for four years. Fans begged Nintendo to remaster The Thousand-Year Door on Twitter, and The Origami King could be the return to the series' roots they've hoped for. The trailer also included something to give fans of another classic Nintendo franchise hope. Here's the Paper Mario Metroid teaser, explained.

Why Paper Mario's Metroid Reference Could Be Teasing A New Game

After the game's title card, the Origami King trailer shows Mario putting on a paper-mâché version of Samus Aran's iconic Metroid helmet. As he pretends to blast enemies with Samus' arm-cannon, the characters with him remark, "That's something you don't see every day. [...] Is he...battling something?" Other paper-mâché masks are seen in the background, too, but the trailer focuses on Samus'.

Previous rumors suggested new Paper Mario and new 2D Metroid games were in the works. While these rumors are unconfirmed, the announcement of a new Paper Mario could lend them credibility, so it's possible a Metroid announcement may be on the way. The reference itself is also quite suspicious. The fact that the character says "something you don't see every day" could be referring to the relatively few Metroid games fans have gotten over the years, and "battling something" could be meant as a teaser for fans: What is he battling? The main enemy of the new Metroid game, maybe?

Obviously, this is all speculation. But given Nintendo's aforementioned lackluster 2020 schedule, a new Metroid game wouldn't be totally out of the blue. If the June Nintendo Direct is indeed cancelled (if there ever was one in the first place), Nintendo might instead release individual trailers like this one to announce new games. Perhaps fans could soon see a surprise-dropped Metroid trailer, as well.

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Paper Mario: The Origami King releases for Nintendo Switch on July 17, 2020.