While the firstborn cub of the monarch is destined to become the next king or queen of the Pride Lands, the second-born cub is tasked with leading the Lion Guard, a group dedicated to preserving the kingdom and defending the Circle of Life. As its leader, the second-born cub is expected to be the fiercest of the group and is thus gifted with the Roar of the Elders by the Great Kings. When the leader of the Lion Guard uses the Roar of the Elders, all the ancient kings roar along with him or her, instilling real power in the cry.
Since the Great Kings provide the power behind the roar, they control its use. It is to be used for good only and can be taken away if the user does not respect his or her gift, as is the case with Scar.
Before the events of The Lion King, Scar was the leader of the Lion Guard and possessed the Roar of the Elders, as he was the second-born cub of the monarch. However, the power quickly got to his head, and he thought himself more worthy of being king than his older brother, Mufasa. When he tried to employ the rest of his Lion Guard to help him overthrow Mufasa, they refused, and he destroyed them. Seeing this, the Great Kings snatched back his power, for they had never intended for the roar to be used for evil.
Kion, the second-born cub of Simba and Nala, is given the Roar of the Elders. When his best friend, Bunga, is trapped by a pair of hyenas named Cheezi and Chungu in the Outlands, Kion uses his power to free him from their grasp. Rafiki and Simba happen to overhear the Roar, and they come to the conclusion that Kion is the leader of the new Lion Guard.
After Kion assembles a team, he attempts to show them his powerful Roar, but the power refuses to work. However, the Roar returns to him in the final battle against Janja's clan, in which Kion uses the Roar to send the hyenas scurrying back to the Outlands.
When Kion and his hyena friend Jasiri get cornered by Janja's clan, Kion warns Jasiri to step behind him. Though hesitant, she does as he asks, and Kion unleashes the Roar of the Elders, driving back Janja and his clan. As Janja lies winded in the dirt, he mutters about how much he hates the Roar, and Kion comes up to stand over him. Thoroughly intimidated, the hyenas scurry off.
When the Lion Guard encounters a hyrax trapped in a thorn hedge, Bunga suggests that Kion use the Roar of the Elders to free it. Fuli reminds Bunga that the hyrax would be flattened, and Kion agrees, suggesting they try another method.
Later, the arrogant leader of the crocodiles, Makuu, angers Kion, and the cub nearly uses the Roar of the Elders. However, he stops himself just in time, not wanting to be like Scar. Despite his friend's protests, he insists that there must be another way.
Finally, Kion decides that he should demonstrate the Roar to scare off Makuu, and he roars into an empty grove of trees, effectively intimidating Makuu, who decides to take his float elsewhere.
After the Lion Guard helps save a family of baboons, Kion seeks counsel with his grandfather, Mufasa. He asks the great lion if he should use the Roar of the Elders to blow away the rest of the thunderstorms, but Mufasa gently reminds him that the rains are needed for the coming dry season.
Kion is later forced to use the Roar of the Elders when he and his friends are trapped in a canyon with floodwaters bearing down on them. After ordering the other animals to stand behind him, Kion roars, redirecting the floodwaters in a safe direction.
When Kion leads the Lion Guard into a canyon, Janja and his minions drop rocks on either side of them, trapping them in the ravine. After gloating to Kion, Janja rushes off to pick off a zebra herd, and Kion and his friends attempt to escape the rock walls. Just in time, Ono, who had been absent, appears, and Kion instructs him to move the zebras so that he can safely blast the rocks with the Roar of the Elders. Ono does as instructed, and Kion breaks the Lion Guard free.
When the Lion Guard races to Fuli's rescue, Kion uses the Roar of the Elders to blow Mzingo's flock away.
When a family of zebras is about to be swept over a waterfall, Kion jumps down a tree branch hanging beside the falls and roars. The force of the blast sends the zebras flying up to safety.
One night, the Lion Guard mistakes a pack of aardwolves for hyenas. Kion steps forward and demands that the aardwolves leave the Pride Lands, using the Roar of the Elders to blow them into the Outlands.
When Janja and his clan invade the Pride Lands, Kion uses the Roar of the Elders to keep them from hurting a herd of wildebeests. Later, Nne and Tano corner a herd of oryxes in a dead-end canyon, and Kion uses the Roar to keep them from harming the herd.
Zira instructs Kion to use the Roar of the Elders on a lone cloud, and when Kion does so, it causes the cloud to briefly turn into a rainstorm. Due to her past friendship with Scar, Zira is knowledgeable of the Roar, and uses that knowledge to try and sway Kion to her side. When he refuses, she decides to hold him against his will and mockingly warns him that if he uses the Roar against another lion, like Scar did against his Lion Guard, then Kion will lose the Roar as well.
However, the rest of Kion's Lion Guard and Jasiri arrive to help, and Bunga reminds Kion that Scar lost the Roar because he used it for evil, not because he used it on other lions. With this reminder, Kion uses the Roar against Zira and her lions, sending them (except for Kovu) flying farther out into the Outlands.
When Kion finds his mother Nala surrounded by hyenas, he uses the Roar of the Elders in rage to save her. The Roar rebounds and opens a cliff in the ground, which nearly swallows Nala. Though Kion manages to save his mother, he feels guilty about having nearly hurt Nala and refuses to use his power again.
When Makuu the crocodile learns this, he invades the floodplains. Kion arrives with Nala, who is taken captive by the crocodiles. Nala encourages her son to trust himself, and Kion successfully uses the Roar of the Elders to defeat Makuu without hurting Nala.
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