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Intro. XTale! Chara (also known as Cross! Chara when she's with Cross in his ghost form, and X-Event! Chara, or more simply XChara) is the tritagonist in the XTale and Underverse universe. XTale! Chara was originally the son of XGaster, and after Ink! Sans shows him the multiverse, XGaster begins his experiment with XTale. With each new timeline, someone related to XTale! Chara died thanks to XGaster. After a few more timelines, XTale! Chara tried to rebel against XGaster, but he is defeated and ends up being XGaster's experiment, the X-Event, granting him his Overwrite powers. To keep his neglected brother alive, however, he overwrites himself in XTale! Frisk. Rebels again, they attempt to plot against XGaster, but failure to formulate a plan with what they now call Cross results in XGaster's escape and Cross absorbs him from an XTale! Frisk dying, destroying the universe in the process. During the first half of season 1 of Underverse.

X-Chara

@Kevin Black