"Mysterion Rises" is the twelfth episode of Season Fourteen, and the 207th overall episode of South Park. It originally aired on November 3, 2010. Mysterion's true identity was revealed in this episode.
This episode is the second of a three-part arc that began with the episode "Coon 2: Hindsight". Led by Mysterion, Coon and Friends are working together to help the people in the Gulf of Mexico, who are at the mercy of the dark lord Cthulhu. The Coon, scorned by his fellow super heroes and now working alone, is out for revenge.
The episode starts off with a comic book montage of the Coon and Friends and Mysterion, who explains most of what happened in the previous episode. Coon and Friends, now led by Mysterion, are holding a bake sale to aid those in the Gulf impacted by Cthulhu's arrival at the end of said episode. They meet a strange man who states that their efforts to stop Cthulhu are futile.
Meanwhile, the Coon is at the airport, as his flight is delayed because Cthulhu defecated on the runway. A little girl asks him if he knows Mint-Berry Crunch, leading him to attack her. Coon and Friends then return to find that Captain Hindsight has ransacked their base looking for incriminating photos of him with Courtney Love. The boys reveal the pictures are fake and solely constructed by the Coon as blackmail, but Hindsight is too conflicted to believe them.
Hindsight pulls out a gun and demands them to tell him where the photos are. Mysterion tells Hindsight that if he doesn't believe them, he has no choice but to pull the trigger. All the other heroes are shocked by this, and The Human Kite inadvertently says, "Dude, Kenny, chill out!", finally revealing Mysterion's identity.
Meanwhile, The Coon tries to get the attention of Cthulhu, but fails to do so. Captain Hindsight explains that he is growing tired of the burden placed on him by his powers, as they only work after a disaster has occurred, prompting Kenny to explain that he too has been cursed with an ability of his own. It is revealed that every time he dies, he simply wakes up in his bed the next day restored to full health. Furthermore, nobody remembers his death, even if they witnessed it first hand, which stuns Hindsight and makes his power seem mediocre in comparison. Kenny is upset with his curse, and tells Hindsight that he is the last person to talk to him about curses.
A LeBron James commercial parody then occurs with Tony Hayward, Mysterion, and Cartman. It ends with Hindsight deciding to remove his powers and Cartman deciding to be cute and adorable to manipulate Cthulhu rather than to be mean and demanding. After introducing himself as "the little Coon" and rubbing Cthulhu's belly (parodying Studio Ghibli film 'My Neighbor Totoro'), Cartman befriends Cthulhu. He then calls a press conference and declares them the new, and this time trademarked, "Coon and Friends". Captain Hindsight is back to being Jack Brolin, a reporter for the news and tells the people that a "rumor" states that Hindsight removed his powers for good. An innocent with an injured arm then cries for help from Captain Hindsight yelling "Where are you Captain Hindsight?" This makes Captain Hindsight realize that "Hindsight" shouldn't have done what he did.
After Coon and Friends learn about a cult that worships Cthulhu at Jim McElroy's house, they find out that Kenny's parents were a part of it. Betsy Donovan then calls for Clyde to take out the garbage. Mosquito pulls the vuvuzela off his nose and says "Alright, just gimme two minutes." (revealing Clyde to be Mosquito). Kenny (as Mysterion) then goes over to his house, only to find his parents smoking crack. He asks his mom and his dad about their involvement with the Cult of Cthulhu, and they state that they were only in it for free beer - something that Kenny doesn't find very hard to believe. Mysterion learns of the whereabouts of the South Park chapter. Together with the other heroes, they go to the Cult meeting, and notice familiar faces (Mr. Adler, the Goth Kids, and the Star Trek nerds). Kenny, however, becomes alarmed over a line they say, "That is not dead can eternal lie, and with strange aeons even Death may die." He abandons his friends and confronts the goth kids in an alley about what it means. The leader of the cult then shows up and asks for the goth kids' assistance in dispensing of Mysterion by order of Cthulhu, who had asked for Mysterion to be disposed of. Meanwhile, Cartman and Cthulhu are flying through the air. Along the way, images are shown of the two destroying various things (a synagogue, hippies, and San Francisco) that Cartman hates. Back in the alley, the goths, Nelson, and the cult leader advance on Mysterion. Coon and Friends show up, but it is too late, for the leader takes Kindergoth's switchblade and stabs Kenny in the chest.
Inevitably, Kenny wakes up in his bed, unharmed. Toolshed, The Human Kite, Iron Maiden, TupperWear, Mosquito, and Mint-Berry Crunch show up at his bedroom door asking him why he ran away and that they have to defeat Cthulhu, completely unaware of the fact that he just died. Kenny then sighs, thus ending the episode.