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The Strange Cobra is a minor antagonist of the The Lion Guard special Battle of the Pride Lands. He was an unnamed blue cobra who was the right-hand minion of the Strange Lion.
What of the Strange Cobra's origins were unknown, but given to the fact that he appeared in the Outlands, it seemed likely that he may have came far away from the Pride Lands and Outlands. According to Scar as he explains his story to a cobra named Ushari, the Strange Lion was first seen when an adolescent Scar (who was the leader of The Lion Guard) was scouting the Outlands.
Upon learning that Scar is second-best in power to his older brother Mufasa (who was King at that time) and that he has a special power called the Roar of the Elders, the Strange Lion claimed that he had wisdom and power, and that with the help from Scar and the Roar, they could take over the Pride Lands and rule everything in a duumvirate. Scar finds the idea to be intriguing, but as he follows the Strange Lion to a volcano, the Strange Lion sets up an ambush by having the Strange Cobra to attack Scar on right eye, which gave him his trademark scar.
As Scar fumes in pain due to the venomous bite, the Strange Cobra smirks at this as the Strange Lion reveals his true colors by attempting to blackmail Scar into serving for him in exchange for the cure of the venom. However, being enraged of being set up, Scar instead uses the Roar of the Elder to kill both the Strange Lion and Cobra, sending them away into the lava river behind to their deaths. Returning to Pride Rock, Scar explained his story to Mufasa and expected to be praised for stopping the Strange Lion's attempted coup d'etat, but Mufasa just friendly patted Scar while giving his nickname.
While the Strange Cobra and the Strange Lion were never able to proceed with their plans to take over the Pride Lands, their attack on Scar, coupled with the cobra's venom slowly poisoning his mind, makes certain one thing about them: they are indirectly responsible to make Scar turn into the selfish and traitorous tyrant he later became.