Prior to release of his name, he was known as "Bald Man", "Old Man", or most commonly "Unknown Elder Mage" or "UEM". Some fans affectionately refer to him as "Baldinort" after the release of his name, in order to distinguish him from the current Xehanort.
He will be portrayed by Chikao Ohtsuka, who previously played Captain Hook in Kingdom Hearts and Kingdom Hearts Re:Chain of Memories. Incidentally, the actor's real-life son, Akio Ohtsuka, portrays the Xehanort most fans are familiar with, as well as his Heartless. Aside from a penchant for playing evil old wizards and scientists, Chikao Ohtsuka was probably chosen for his character's as-of-yet unrevealed association to his son's character.
Sometime, either early in the story, or before it entirely, Master Xehanort disappeared alongside his enigmatic apprentice. The details of their disappearance are uncertain as of yet, but it is known that it foreshadows a great disaster in the universe of Kingdom Hearts. Apparently, he is in search of the Princesses of Heart, and judging by the trailer Birth By Sleep, he is also seeking Kingdom Hearts.
During the course of the game, he meets alone with Terra in the Gathering Place. He seems ashamed about his apprentice's lust for dark power, almost sorry, and perhaps lets on that he is not quite as evil as some may think.
Eventually, he faces off against the three warriors, alongside his apprentice. He utilizes incredibly powerful magic, especially what appears to be a blizzard magic that can completely freeze a person. He also wields a hefty keyblade ambidextrously and moves with amazing speed. Terra and Ven stand no chance against him during the duel.
As the duel comes to a close, he turns his Keyblade into a ball of energy and uses it to summon a blue Kingdom Hearts in the sky.
Master Xehanort's very appearance has given rise to speculation. He appears as an old man, quite bald except for thin eyebrows and a long white goatee. His ears are pointed and his eyes are amber-gold, traits that Xehanort, Xemnas, Xigbar, and Saix share. He has broad, hunched shoulders and a crooked back, belying his abilities.
His attire is quite familiar. It is nearly identical to the clothes that Xehanort's Heartless wears in the first Kingdom Hearts. This, along with his name, have given rise to immense speculation as to the nature of the connection between the two.
Despite his bent and fragile appearance, Master Xehanort appears to be one of the most powerful figures to show his face in the Kingdom Hearts universe.
He has the unique ability to wield a Keyblade, and does so with amazing skill and finesse, fighting with both hands, and needing only a flick of the wrist to fend off Terra's powerful strikes. His Keyblade is quite obviously a work of evil, with the dark eye apparent on Riku's Soul Eater, a black finish, a spiky shaft, and a head resembling the blade of a battle axe. He also appears to have immense power over the Keyblade, as he can control many at the same time from afar, summoning dozens of them to form a destructive storm that moves as he wills it.
He is also a very powerful mage. His earth magic is powerful enough to create cliffs from a bare plain, and his blizzard spell is enough to completely freeze Ven solid.
He also has an as-of-yet unseen power involving the Keyblade. He can turn it into a ball of blue-purple energy that can be fired into the sky, apparently unlocking Kingdom Hearts itself.
The extent of his power is not yet known, but it is apparently stronger than anything the three heroes of Birth by Sleep have yet had to face.
The mysterious Master Xehanort has opened the world to many different assumptions.
- One of the most common theories involves him possessing Terra. Due to Terra's similarities to Xehanort and his Nobody Xemnas, it is believed that Master Xehanort was consumed by the power of Kingdom Hearts, and his spirit went on to Terra, whose eyes subsequently turned yellow from the overwhelming darkness entering his heart. Terra then lost his memory and ended up in Radiant Garden, where all he could remember was his possessor's name, and became the man we know today as Ansem, the Seeker of Darkness. However it would make little sense since Terra shows up in Kingdom Hearts II Final Mix+, or so one would think. Nomura has stated that the Terra fight is irrelevant and can be seen as far more of just a bonus fight than anything pertaining to the plot of the games. Most people believe that that enigmatic soldier was merely a wandering figure or physical manifestation of a part of Terra that could be still left alive somewhere, such as a manifestation of Terra's memories possibly.
- Xehanort may be the first Dark Keyblade wielder. His appearance makes it look like he is a denizen of the Realm of Darkness himself. He may be possessed by an even greater evil though.
- Xehanort is the anagram of either No Heart or Another. (not including the letter X)