Ventus

Ventus, also known as Ven, is one of the main protagonists in Kingdom Hearts Birth by Sleep and Kingdom Hearts Birth by Sleep Final Mix. He was a Keyblade wielder before Sora ever became one, and was apprenticed to both Master Xehanort and Master Eraqus. He is the youngest of the trio composed of Terra, Aqua and himself.

Ventus' heart was severely damaged by the creation of the pure being of darkness in his heart, Vanitas, who was created by Xehanort releasing the darkness from his heart, and then again when the X-blade forged from their hearts is destroyed. Both times, Sora's heart reaches out to mend Ventus's heart, and by the end of Kingdom Hearts Birth by Sleep, Ventus' heart has gone to sleep within Sora so that it can recover until it is fully healed and ready to rejoin his body, which lies comatose but safe within the Chamber of Waking.

Why He Rocks

 * 1) He has a personality that is very identical to Sora. As he is a very cheerful and likable protagonist who is willing to step into any risk to save his friends.
 * 2) He is a very well trained Keyblade wielder who wields his Keyblade in a backhanded position that is pretty impressive.
 * 3) He and his friends Terra and Aqua can be to travel to other worlds using their Keyblade Armor, and turning their Keyblades into Keyblade Gliders. Which is an impressive feature since they don't have to get to worlds using Gummi Ships.
 * 4) He and his friends risked their lives to try and stop Master Xehanort from triggering another Keyblade war. Which makes each of them a really great hero.
 * 5) He started off as a boy who's heart was literally broken by Xehanort's darkness extraction, but he now has come a long way due to his new found experience with the Keyblade, his friends, and his connection with Sora.
 * 6) He managed to successfully defeat his dark half Vanitas, destroy the X-Blade, and stop another Keyblade War from being triggered. But in the process, the X-Blade's destruction caused Ventus's heart to leave his body, and went into Sora's until it is fully healed to join back with his body, which is currently sleeping in the Chamber of Waking at Castle Oblivion.
 * 7) He is one of the Seven Guardians of Light that is destined to battle the Thirteen Seekers of Darkness known as the True Organization XIII in the upcoming Kingdom Hearts 3.