(This is just the stuff that's actually part of the UT universe) W.D. Gaster served as the royal scientist prior to Alphys. Then, one day, fell into one of his own inventions, which is speculated to be either the Determination Extraction Machine or the core itself. This incident resulted in Gaster being fragmented across both time and space, leading to his possible identities as the enigmatic "Mystery Man" or the obscured figure known as "Redacted." Among these possibilities, "Redacted" emerges as a more compelling candidate due to his unique communication style, which is expressed through the cryptic Wingdings font. This detail not only adds depth to Gaster's character but also reinforces the theme of undefined existence within the game’s narrative.