Nintendo Power are competitors in the King for Another Day Tournament. They are the duo of Reggie Fils-Aimé and Bill Trinen.
- "No one's body is ready for the true might of Nintendo Power! After Reggie retired, Miyamoto decided Reggie needed a boost from inside the company, and Bill Trinen is the perfect match. Now that these two gaming industry legends have brought their Joy-Cons together, this tournament has truly been switched on!"
- —Nintendo Power's description on the MOJO!!
Nintendo Power was originally conceived as a pair-up of Reggie and Etika by the name of The Joy-Con Men, whose rips would consist of music from the Fire Emblem, Xenoblade, Animal Crossing, Wii Fit, and The Legend of Zelda franchises. However, the team announced in "SiIva Direct • SiIva Lighthouse Live ∣ E3 2019" that his character would not be in the tournament, as the real Etika was publicly struggling with mental illness, and the team was concerned that the tournament could bring him unnecessary or negative attention.
The team's new incarnation as Nintendo Power was revealed in "SiIvaGunner: King for Another Day Tournament Direct 9.21.2019". The already-revealed sources remained the same, but with the addition of music from Nintendo system software and presentations, such as music from the Nintendo eShop and Wii channels and Nintendo Direct jingles.
Lines in bold were used in the tournaments.
- In their art, Bill is seen reaching for a donut, referencing this video.
- This is the only pairing with both a newcomer and a veteran.
- In DJ PROFESSOR K vs. NINTENDO POWER [W R2 M8], their victory quote was used against DJ Professor K instead of their vs. quote.
- Their victory quote against Metal Ajit Pai references the Reggie Mech from Reggie Fils-A-Mech - Nintendo @ E3 2014.
- Their victory quote against Geno references "The Grinch" leak which had Geno as one of the "fake" characters announced in it.
- Their quotes against Weird Al, Johnny Bravo, HOBaRT and Rhythm Masters, reference the various Yo-Kai Watch sketches where Bill and Reggie get possessed by various Yo-Kai Watch spirits during a meeting. The first one has Bill eating all the donuts, the second one has Reggie and Bill insulting each other, and the third one has Reggie dancing.
- Their vs. quote against Pitbull and the Aliens is directly taken from the ending of Nintendo - Get Ready for E3 2015!
- Their vs. quote against Adam Levine is a reference to the song "Just A Feeling".
- Their victory quote against Adam Levine is a reference to his song “Sunday Morning”.
- Their vs. quotes against Mariya Takeuchi and Donkey Kong reference farewell gifts Reggie received after his departure from Nintendo, a plastic ass and art piece from Retro Studios respectively.
- Their vs. quote against Daft Punk ft. Pharrell is a reference to one of Daft Punk's songs "Harder, Better, Faster, Stronger" being an overused song heard in Flipnote Hatena videos.
- Their victory quote against Daft Punk ft. Pharrell references an in-game scene shown in the Tomodachi Life Direct 4.10.14.
- Their vs. quote against Papyrus is a reference to the reveal trailer of the Switch port of Undertale.
- Their vs. quote against Jack & Elmo references a series of skits from the 9.1.2016 Nintendo 3DS Direct.
- Reggie's victory quote against MissingNo. references a line from the Nintendo E3 2004 Press Conference.
- Their victory quote against Eminem references a song he’s appeared in called “50 Cent”.