Scar is an antagonist in Kingdom Hearts II. He is Simba's evil uncle, and was jealous of the admiration and power his older brother Mufasa recieved, so he killed him in order to take his place as king of the Pride Lands. Scar eventually becomes a Heartless, but retains his appearance and personality.
He comes from the Disney movie The Lion King.
 Kingdom Hearts II
Kingdom Hearts II lays host to the story of Scar's rule over the Pride Lands. Scar teams up with Pete as a way to rule the kingdom with discipline. Scar is the King of the Pride Lands, and when he first meets Sora, Donald, and Goofy at Pride Rock, he wishes to eat them, as there is little food in the Pride Land because of his rather shoddy treatment of them. The trio escape and convince Simba to return to Pride Rock.
When this occurs, an overconfident Scar reveals the truth about Mufasa's death, enraging Simba and prompting him to chase after his murderous uncle. While Sora, Donald, Goofy, Timon and Pumbaa hold off the Hyenas, Simba fights Scar at the top of Pride Rock. Sora and co. arrive in time to watch Simba throw the pretender to the throne off the cliff, but Pete arrives and tells them that because of the anger and jealousy within his heart, Scar has become a Heartless. A battle ensues as Scar climbs back up to the peak, with Sora and the gang victorious.
In the second visit to the Pride Lands, Scar appears as a dark ghost which haunts Simba, taunting him and saying he will never be a true king. The ghost lives as long as Simba has doubt in his heart. Eventually Simba retreats to the oasis in the jungle, but Scar's ghost confronts him there as well. With the help of Sora, Donald and Goofy. Simba stood up to the ghost and it disappeared. The victory was short-lived however when Timon arrives and tell them that Scar's ghosts are all over the Pride Lands and everyone but Nala have escaped. The group returns to the Pride Lands and Simba saves Nala from the ghost.
Immediately afterward, all of the ghosts merged in the Savannah and becomes the enormous Groundshaker Heartless. Sora and Simba fight the giant Heartless and emerge victorious, the ghost of Scar is finally gone.
Scar is depicted as a cold, ruthless, brutal, and merciless tyrant whose sole goal is to be the ruler of the Pride Lands. The lives of his subjects, and even his family mean nothing to him. To that end, he is willing to put whatever he pleases on the line, and kill anyone who gets in his way. This is seen when he murders Mufasa in cold blood. He is also shown to be arrogant and overconfident, as seen when he foolishly admits to killing Mufasa, a trait which proves to be his downfall as he ultimately pushes Simba too far.
Scar is an adult lion with brown fur and a thin, silky, coal black mane. The fur on his belly, the bottoms of his paws, and around his mouth is light tan and when compared to his nephew and older brother he is quite lanky and frail. There are short tufts of black fur on the back of his elbows, as well as on on the tip of his tail, and he has sharp, dark brown claws. Scar's name obviously refers to the scar he has over his left eye. His eyes are striking yellow green and his sclera are yellow, while his eyebrows are the same color as his mane, black. He has a widow's peak and his large, round ears are partially visible through his mane. He has ten dark whiskers, five on either side of his upper lip. He also features a goatee on his chin.
Scar first appeared in the 1994 film The Lion King. Scar is Simba's evil uncle and the king of the Pride Lands after Mufasa's death. When Simba returns to the Pride Lands and admits that he is the one responsible for Mufasa's death, Scar tries to kill him by making him fall off of Pride Rock. Before making him fall down, Scar tells Simba that not Simba, but Scar is the one responsible for Mufasa's death. Simba climbs back up and forces Scar to confess that he was the one who killed Mufasa. After that, Scar and Simba start fighting. As in the game, Simba throws Scar off the cliff, only he survives the fall but is mauled to death by the hyenas whom he had previously betrayed.
 See also