Nintendofan997's color code looks similar to MarioGame2222's, due to the colors used for the cap, arms and shirt, and for the overalls:
Blue sky cap, harms and shirt,
Brown shoes (like Mario, Luigi and a lot of other guys),
Tanned face (slightly darker than regular, as you can see in the picture at the top right corner of this article),
Brown hair (like Mario, Luigi and many other guys).
His eyes sometimes appear green instead of blue (the regular color).
Unlike the rest of the characters, X appears to be more calm and compassionate than the rest. While he does show discomfort towards the shenanigans around him (even towards his closestfriends), he rarely ever loses his cool. A notable exception is War Of the Fat Italians 2019, where he finally gets fed up with Mario and SMG4 fighting each other and not putting aside their differences.
Seaside Stupidity Part 1 shows him to be rather cowardly, as he decides that it's every man for themselves after a sea monster ends up causing the cruise ship he was riding on (along with many other passengers) to sink. He later attempts to persuade A.S Swipe to kill Mario instead of him, only for Mario to retaliate by saying that he should kill X instead for being a side character.
Nintendofan997 seems to have a future sight ability which he uses unwillingly to detect danger/dark omens. How he obtained this power is unknown. When he uses this power he seems to experience a lot of pain.
It's implied in the video "The Crazy Fighters" that he also has the power to shoot lasers.
He carried guns with him during early videos as he came from the zombie era.
(Mario stole one prior to the events of Crystal Funhouse).
Nintendofan997 has only one counterpart in bloopers: Nintendofan998 (or Xboxfan998), his evil doppelganger, who is called "Xboxfan996" in SMG4's videos for an unknown reason.
Following Starman's return after the 2012 blooper "The Warrior and the Hobo", X's appearances officially started to become more scarce. It went to the point where he only had about 3 appearances in 2013. Therefore the common statement that he started appearing less after 2014 in invalid.
He rarely makes videos now, but he still post comments and subscribes.
He was formerly known as Xboxfan997 but he changed his YouTube channel username.
Despite his name being different for quite some time, he's still called "X" in SMG4's bloopers.
Xboxfan997 acts as the host in the video "War of the Fat Italians 2013", though he refers to himself as "Xboxfanguy".
It is implied he uses drugs, as in the video "War of the Fat Italians 2013" when Mario and SMG4 go to him to find out who wins, he says "The drugs are over there! Don't hurt me!", implying he is a drug-user.
This is also implied in the video "The Imposter", as SMG4 states he is on crack again when the impostor (X) is chasing him.
He has over 10,347 subscribers
He and SM64 were the only non-fictional Youtubers to be infected by the T-Pose Shroom.
While Nintendofan997 is called "X", he is not to be confused with X, a villain who stole Mario's body in the episode "Enter X".
He has appeared in every War of the Fat Italians as the judge except the 2018 edition, due to being T-Posed. Waluigi takes over the judge role instead.