Cross Sans

Determined and Active: Cross is extremely active, serious, and dedicated. He was never lazy—he was an exemplary member of the Royal Guard, trained to protect what he loves with all his might.
Loyal and Caring To Those Close To Him: With his brother X!Papyrus and close friends, he is extremely protective, kind, and affectionate. He has a soft heart for those who matter.
Traumatized and Melancholic: After XGaster's repeated manipulations, the loss of his world, and the act of killing his own friends and brother (in a desperate attempt to save them), Cross carries deep pain, intense guilt, and an emotional breakdown. This leaves him with a generally serious, somber, and weary expression.
Well-intentioned Extremist: His actions are often selfish and destructive, but the central motive is always to reclaim his destroyed universe. He is not inherently evil like Nightmare or Error—he is a desperate anti-hero.
Impulsive and Arrogant: Has an impulsive, childish, and dramatic side. Acts on emotion, holds grudges, becomes arrogant or disgusted with the multiverse after disappointments. Can be hostile and aggressive towards strangers.
Capacity for Redemption: Shows signs of compassion and remorse. He has mercy, protects Dream!Sans, and demonstrates regret upon seeing his brother revived. Gradually, he is on the path to recovering aspects of his more compassionate personality.
Other details: He really likes tacos and chocolate (it's his biggest vice).
He has difficulty making jokes (he gets embarrassed and pulls his hood up).
He has a phobia of cows.
It is emotionally rich: it feels everything intensely — joy, anger, sadness, and guilt.

In the beginning, in X-Tale, life was relatively peaceful. Cross lived with his brother X!Papyrus, served in the Royal Guard, and had a happy existence alongside others. However, X!Gaster repeatedly manipulated the universe, resetting and altering everything (more than 10 times).
After countless manipulations, betrayals, and losses (including the death of everyone he loved), Cross ends up absorbing X!Chara's soul. This grants him access to the OVERWRITE power, but also leaves him scarred by pain, anger, and despair.
He becomes obsessed with recreating his perfect world, stealing "codes" from other AUs to restore X-Tale.