Francis Xavier Atencio (born September 4, 1919), most commonly known as X Atencio, is a former animator, composer, and Imagineer for The Walt Disney Company. Walt Disney valued quality artists, like multi-talented Xavier Atencio, who helped animate Disney classics, including Fantasia, and later developed music for such Disneyland attractions as the Haunted Mansion (for which he co-wrote the song "Grim Grinning Ghosts"), and Pirates of the Caribbean. Atencio recalled the day Walt first greeted him with a robust, "Hi ya', X!" Walt's acknowledgment by name (Xavier, by initial, which was his nickname at the Studio) was a thrill to the young artist and future Imagineer. X recalled, "Walt was a father image. You felt good merely having been in the presence of his dynamic personality."