Young Xehanort

Young Xehanort is the main antagonist of Kingdom Hearts 3D: Dream Drop Distance. He was introduced as an optional boss in the North American, PAL, and Final Mix versions of Kingdom Hearts Birth by Sleep, and he reappears throughout Kingdom Hearts 3D: Dream Drop Distance as an obstacle to Sora and Riku's Mark of Mastery exam.

As his name implies, Xehanort is a younger incarnation of Master Xehanort, first seen in the prologue of Kingdom Hearts Birth by Sleep. By acquiring the ability to travel through time from Ansem, Seeker of Darkness, Xehanort comes into conflict with Keyblade Wielders of several generations, such as Sora, Riku, Mickey, Lea, Terra, Aqua and Ventus.

Before Kingdom Hearts Birth by Sleep
As his present-day incarnation, Xehanort lives his early years on Destiny Islands. Xehanort is paid a visit by the future incarnation of his Heartless "Ansem". Gaining the ability to traverse time, Xehanort proceeded to assemble the true Organization XIII with his many incarnations.

Kingdom Hearts Birth by Sleep
After defeating the Vanitas Remnant, Terra, Ventus, and Aqua each separately return to the now-ruined Land of Departure, where they encounter Xehanort, his face hidden by his hood. Xehanort draws his weapons and attacks, but after an intense battle, he walks away and disappears.

Kingdom Hearts 3D: Dream Drop Distance
A decade later, Xehanort comes into conflict with Sora and Riku in the Dreaming Realm during their Mark of Mastery exam, encountering them across several sleeping worlds, and accompanied by figures such as Ansem, Xemnas, and Vanitas. Eventually, Xehanort confronts Sora again in The World That Never Was, where he traps Sora in an illusion of his first meeting with Ansem, revealing his true identity to Sora at last, as well as his goal. After Sora's heart is damaged following a fight with Xemnas, Xehanort takes Sora's comatose body to the castle to be used as the thirteenth vessel for Organization XIII.

Riku later comes looking for Sora and finds him, but Xehanort stands in his way, even impervious to Mickey's Stopgun spell. Xehanort brandishes his Keyblade and fights Riku. Though he is defeated, Xehanort merely takes his place in one of the thrones of the Organization. He flees the scene with Master Xehanort and the others when reinforcements arrive to save Sora from his fate.

Appearance
Young Xehanort has mildly tanned skin, golden eyes, and silver hair which both slightly spikes and falls past his shoulders in the back; it is styled similar to Terra-Xehanort's, albeit with four bangs framing his face, the back two thicker than the front two, and the two backwards spikes on the sides are absent, the topmost one slicked back. Save for a flashback scene, in which he sports the same clothes as his alternate timeline counterpart, Xehanort is clad in the Black Coat commonly associated with Organization XIII, and when he first appears in Kingdom Hearts Birth by Sleep, he wears the hood up, very similar to Xemnas in Kingdom Hearts Final Mix.

Interestingly, in Kingdom Hearts Birth by Sleep, Xehanort's body model is a copy of Saïx's.

Abilities
He wields two weapons that bear a striking resemblance to Xemnas's Ethereal Blades, but appear to have hilts, which many of Xemnas's blades do not. The blades are made of light blue energy and the black handles are somewhat reminiscent of the Terminus and Ruination Ethereal Blades. The blades can be combined into a dual-blade, and extend to be lashed out like a whip. Xehanort wields these weapons with a reverse grip, similar to the unorthodox way Ven wields his Keyblade.

In Kingdom Hearts 3D: Dream Drop Distance, Xehanort wields these weapons again, along with the No Name Keyblade. He retains his ability to control time, demonstrated by several strikes which temporarily slow his opponent down, and fights in an arena which gives him control over basic elements, such as Fire and Blizzard. He is able to teleport himself around the battlefield like Master Xehanort, and delivers swift, powerful strikes similar to Terra-Xehanort. Another trait is his ability to fire projectiles very similar to those fired by Sora in Wisdom Form.

But arguably Xehanort's most controversial trait is his ability to suffer a defeat, yet turn back time to the start of the fight, as evidenced in his battle with Riku.