Ultimax's tournament title, the P-1 Climax, is a nod to New Japan Pro-Wrestling's famous annual fall tournament, the G1 Climax. The Midnight Channel video features a wrestling stage and arena similar to one used at New Japan's Wrestle Kingdom events, and the logo on the screen is vaguely similar to the company's "lion mark" logo. Furthermore, the enemies' insistence that every match be one-on-one, fair and square, fits exactly with the G1's intent.
Adachi has a palette that takes clear inspiration from The Joker. Guess what Adachi's arcana is.
The fact that Junpei wears his cap backwards may bring to mind Ken Griffey, Jr., who often wore his cap that way throughout his career.
Shadow Akihiko will descend from the sky in a ball of purple energy in one opening animation, referencing a Magneto animation from Marvel vs. Capcom.
A part of Teddie's auto-combo has him do Rapid-Fire Fisticuffs while suddenly growing thick eyebrows, which makes him resemble Kenshiro. Incidentally, Arc Sys also worked on a Fist of the North Star fighting game.
After revealing a fake Kanji to be, well, fake, Yukiko and Teddie strike a pose that brings Phoenix Wright to mind.
One of Shadow Labrys' palettes bears a very close resemblance to Noel Vermillion. Naoto and Adachi have palettes based on Hazama and Yuuki Terumi, respectively.
