Overwrite

About
Overwrite is an paramount tool designed by XGaster. This button is held within the soul of XGaster, and anyone containing any parts of the soul can attain access to the button. Overwrite can change an entire timeline and everything within it forever. However, XGaster was unaware of the consequences of making such a powerful item. After the creation of Timeline X, he was no longer in control of it, or the X-Event after he perished. (After Underverse 0.4, he was rekindled and had control over his soul again.)