Simon seems to have accepted this and wants to use his final hours to create a time portal to the past to contact Betty and apologize for driving her away.

Marceline and Simon are overjoyed to see one another, but Marceline becomes concerned with Simon's health as he is dying. She faints from shock, but when she comes to, she convinces Finn and Jake to go help Simon. Simon tells her what's happened, that he needs her help and to bring Hambo with her. He calls her up immediately while she is in a jam session with Finn and Jake, neither of whom care for her new style of holding her bass guitar higher up to get better fingering.

He finds a book on mystic rituals that he and his fiancée, Betty Grof, wrote together, and finds a picture of a young Marceline inside. He flies into 'The Past Room,' finds an old pair of his glasses, and accesses a secret passage to a library, containing all his research and old clothes. Simon punches him and knocks him out, apologizing as he takes Ash's magic carpet, leaves Wizard City to go to the Ice Kingdom. He states that Simon is in his usual busking spot and to get lost.

He is then confronted by Ash, Marceline's ex-boyfriend, who insults him by telling him he is ugly and to stop looking at himself in a puddle of water. He believes he is hallucinating until he removes the crown and finds he is still thinking rationally. Grand Master Wizard sends the Wizard Police to attack Bella Noche, to little effect, while Simon escapes, still in shock, from the chamber to the streets. Bella Noche uses this distraction to absorb the power of the magical items, just as Grand Master Wizard breaks in, declaring that Bella Noche must not enter their world, as he is 'a being of pure anti-magic.' However, it is too late as Bella Noche strikes, removing the magic from the four congregated wizards, which leaves Ice King's crown powerless and turns him back into a young Simon Petrikov. Interested in this reward (and in joining the secret wizards' club), Ice King reveals himself, much to the other wizards' annoyance. In exchange for bringing the powerful magical items that will allow Bella Noche to enter their realm, he has promised them the lost system of Antediluvian magic, 'the tightest of all wiz biz.' In a secret chamber in Wizard City, the Secret Society of Forest Wizard, Laser Wizard and Bufo meet with Bella Noche, a misshapen head from another dimension, unaware that Ice King is watching them from the shadows.

When a ritual changes Ice King back into Simon Petrikov, he enlists the help of Marceline, Finn, and Jake to recontact Betty in the past to tell her he's sorry for everything he has done.

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