—Dilan to an Unversed
Dilan, misspelled as "Dilin" in the North American version of Kingdom Hearts II, is one of the six apprentices to Ansem the Wise, and the original persona of Xaldin. He appears in Kingdom Hearts Birth by Sleep, Kingdom Hearts Birth by Sleep Final Mix, and in Kingdom Hearts 3D: Dream Drop Distance.
While Dilan appears to bear similarities in personality to Xaldin, given his rather strict nature, his character seems to be much more benevolent and noble than his Nobody, demonstrated when he was willing to defend Radiant Garden from the Unversed and expressed genuine concern for Ventus's well-being after the latter volunteered to fight the Unversed alone (Dilan himself was only stopped from following Ventus by Even ordering him to return to his post).
A strong possibility is that Xaldin's hostile attitude towards Axel shown in Kingdom Hearts II Final Mix stemmed from Dilan's confrontation at the end of Birth by Sleep with Lea, whom he throws out of the castle along with Isa for trespassing.
Dilan is a tall, broad-shouldered man that wears a dark slate grey guard uniform which is adorned with a curled heart symbol, and white gloves. The front of his jacket sports two rows of gold buttons, silver highlights, and a red and white heart like the one on his gloves. He also wears a belt and knee-high boots, both of which are black. Dilan's hair is black and worn in long dreadlocks. He keeps most of his dreads tied into a low ponytail, but one dangles over the right side of his face. He also has thick sideburns (though they do not hook over his cheeks like Xaldin's do), thick eyebrows, and violet eyes.
Dilan wields a single lance with silver edges, a blue head, and a handle that alternates from violet to silver. The curled heart symbol is incorporated into the head of the lance.
Dilan appears with Aeleus, both guarding Ansem's castle, Hollow Bastion, in Radiant Garden. Ventus first encounters them while he is looking for Mickey Mouse, but they refuse to let him in saying that the castle is closed. Dilan suggests that Ven should go home before the monsters get him. Aeleus then spots an Unversed, and both guards are about to attack it. Ventus runs ahead of them and begins chasing it, despite the guards' protests. They were about to go after Ven, but Even comes and openly wonders what will become of the castle if they leave. Aeleus and Even begin to argue, but Dilan reminds Aeleus that their duty is to protect the castle. Even then tells that his Lordship wants to see them and both guards head inside.
Later, Braig brings Dilan and Ansem to an amnesic Terra-Xehanort, along with the Keyblade and armor of a Keyblade wielder. Terra can only remember his possessor's name: Xehanort. While Braig takes Xehanort to the castle, Dilan carries the armor and Keyblade for Braig.
Between Kingdom Hearts Birth by Sleep and Kingdom Hearts 358/2 Days
About a decade prior to Kingdom Hearts, Dilan was still one of six apprentices to the ruler and scientist of Radiant Garden, Ansem the Wise, alongside Braig, Even, Aeleus, Ienzo, and Xehanort. Worried the Darkness in people's Hearts would eventually consume his world, Ansem began performing tests on Xehanort's heart. Eventually, he created a laboratory in his castle's basement for such experimentation, by the urging of Ienzo. However, Dilan and the other apprentices had their own intentions for the laboratory, and began conducting inhumane experiments on the human heart and the darkness within it.
Such experimentation led to the creation of Heartless. Ansem quickly discovered their secret experiments, and immediately ordered them to stop. One day, after being advised to review their research data by King Mickey, Ansem found that the effects of their experiments had become irreversible. Eventually, Dilan and the other five apprentices dabbled too deep into darkness through their continued experiments. Dilan, along with the others, banished Ansem the Wise to the Realm of Darkness.
Xehanort eventualy removed his heart (with Master Xehanort's Keyblade) along with those of Even, Aeleus, Ienzo, Braig, Isa and Lea, to be the first of the thriteen vessels needed for his plans to create the X-blade.
As Xaldin and his Heartless had been destroyed, Dilan was able to come back as a human once more. However, he and Even were unstable following their resurrection in Ansem's lab. Because of this, he and Even were forced by Aeleus to rest longer in an unspecified location in the castle. Aeleus mentions later to Lea that both Even and Dilan are awake, but still unstable.