The original Loki died during the Siege of Asgard. Before that he had manipulated Hela into taking his name out of the Book of Hel, allowing himself to be reborn. Thor, missing his little brother, found a new and much younger Loki in Paris under the name of "Serrure" (Lock in French), without any memories of the original Loki. However, Kid Loki tearfuly claimed to have horrible dreams about his past crimes and was afraid to remember. Thor restoured part of his identity (though he remains in the form of a child) and brought him back to Asgard. However, he was still despised by the other Asgardians and Odin, suffering continuous bullying. When Skadi freed the Serpent from imprisonment Odin, whom Thor had brought back to life to deal with the World Eaters, lead the Asgardians from Midgard into a new Asgard, which he made into a world of war intending to raze Midgard to stop the Serpent. Loki, along with his new pet Ikol, attempted to free Thor, whom Odin had imprisoned. Loki later rode a Hel Wolf into the realm of Mephisto, where he conspired to bring the two together to fight the Serpent.
With the help of Tyr, Loki aproaches the Serpent's Tongue, a messenger from the Serpent, to get some information about his plans. After Tyr kills the messenger, Loki convinces Mephisto and Hela to fight together in order to defend their realms and receives four Dísir to assist him. In order to talk to Surtur, the Dísir kill the Hel Wolf and Loki rides him into Limbo. Realizing that he's dead, the Hel Wolf decides to kill Loki but he is eaten by Surtur instead. The young trickster cuts a deal with the fire demon in order to get a sliver of the twilight Surtur’s sword casts. After that, Loki and Ikol return to Asgard and release the Destroyer and go back to New York where Tyr and the Dísir witness the rise of the Serpent's Citadel. Riding the Destroyer, Loki tells them that they are going to destroy it.