X

X is a white Letter X. He consists of anime-like eyes with large thick eyebrows and an upside down “V” shaped mouth And His Tongue is Gray. He has two lavender ninja bands on the top of his upper diagonal strokes. He resembles a ninja in the style of Japanese anime. Lastly, his asterisk gem sits on his forehead. X is a very brave and resilient ninja warrior. As a child, x was friendly towards many of the other Letters. One day, f, l, and o got into a fight, and l and o made f spell the word "frick". Angered, x punched f with his ninja powers, forcing f to drop the "" (asterisk) gem. Once f was defeated and ran towards his cave, x obtained the "" Gem, which gave him the power to multiply and add. As an adult, X was skilled in fighting like a ninja. After watching F defeat all the other Letters, X challenged F to a duel, multiplying himself into numerous copies of himself. F, who knew he couldn't fight X, dropped his gems for a fair fight. X agreed, dropping his "*" Gem. The two got into battle position, but F snuck past X by breaking the fourth wall and crunched him to his corpse.

As seen in Y, Y cried out in terror after seeing his demise, meaning the two may be close.

But after the events of the epilogue, he still holds his asterisk gem, because he got it before Z reversed the effects of the original timeline. X (then lowercase) was being tracked by 1 in 1 (episode). When 1 successfully captures X, B, M, and Y all step in to save X by using their abilities. X clones himself and uses Y as a slingshot to fire clones at 1 until he takes off. However, it was revealed 1 was merely faking it. He uses one of the calculator buttons, which are jelly-like substances, to capture X. As it turns out, 1 needed X for his asterisk * gem, so he could make a clone of himself to make the equation "1+1=2" in his machine. As such, 2 is created, proving to be stronger than 1. Y, M, and B fail to defeat 2, and soon the calculator ship takes off with X captured.

However, the numbers' success is short-lived as seen in 3, as Z notices the entire commotion and uses his ellipsis gems to ground the calculator ship, after which Lshakes open the ship, releasing everyone, including X.

The following episode, X is later seen trying to take down 1 and his allies, who were using the equation machine as a train to rush over to F's cave. When he attempts to multiply himself, this backfires as he realizes he still doesn't have his asterisk gem, and he gets run over by the equation machine shortly afterwards, injuring him in the process.

M and Y, who both survived their injuries, later encounter him in 5 (episode). He still laments over his failure to stop the numbers, and removes his headband in shame before walking away onto another surface of Z.