The being called Kurse was originally Algrim the Strong, one of the Dark Elves of the extra dimensional realm of Svartalfheim who served the Dark Elves' ruler, Malekith the Accursed. Malekith captured Lorelei, an Asgardian woman who had used a magical potion to make the Asgardian thunder god Thor fall deeply in love with her. To rescue Lorelei, Thor went to he English Cotswolds, where stood the faerie castle that serves as a nexus between Earth and the other dimensional faerie realm of Svartalfheim. Thor broke through into the world of faerie and seeing Lorelei menaced by Malekith, became oblivious to everything else. Hence, he was easily ambushed by the superhumanly strong Algrim, who stood in shadow wearing ebony armor. Malekith had told Algrim he had chosen him to defeat Thor. But while Thor and Algrim fought each other, Malekith ordered that a pitfall be opened beneath their feet. Thor and Algrim fell down a great chasm toward a lake of molten lava. Thor summoned his magic hammer Mjolnir, which carried him to safety, but Algrim plunged into the magma.
The magma's tremendous heat left Algrim on the brink of death. He would have been killed outright except that his enchanted armor protected him from the magma's full effects, and that his desire for vengeance for Thor gave him the will to live. In fact, the shock of the intense pain the magma caused him rendered Algrim amnesiac; not remembering the real reason why he fell into the lava, he knew only that Thor was somehow to blame. Algrim's hatred of Thor was sensed by the incredibly powerful In New York City, Kurse mistook Beta Ray Bill for Thor and attacked him. Bill escaped death at the far stronger Kruse's hands by reverting to his original, non-super-powered form, in which he no longer resembled Thor. Driven by insane hatred, Kurse wreaked havoc in Manhattan as he searched for Thor.
In the process he severely injured Margaret Power, mother of the superhuman children known as Power Pack, who had since recovered. Power Pack sought out Kurse and succeeded in burying him alive by causing the collapse of a building under construction. But Kurse succeeded in freeing himself that very same day, found Thor, and attacked him. Kurse was now stronger than Thor, so Thor donned his belt of strength, which doubled his strength.
The observing Beyonder then vastly increased Kurses' strength so that it again greatly surpassed Thor's. Beta Ray Bill and Power Pack then arrived to join the battle. Thor used his hammer to project intensive heat at Kurse. The heat, reminding Kurse of the lava pit, reawakened his memories of how he came to fall into it. AT last Kurse realized that it was not Thor but Malekith who was responsible and his hatred therefore shifted from Thor to Malekith. On Thor's instructions, Energizer, a member of Power Pack, absorbed energy from both Thor's and Beta Ray Bill's enchanted hammers and then fired a tremendously powerful ball of energy at Kurse, which rendered him unconscious. Thor then suggested to the Beyonder that Kurse be transported to Hel, the realm ruled by the Asgardian death goddess Hela, to search for Malekith, who might be there. Thor was hoping that Kurse would cause trouble for Hela while he was there. The Beyonder agreed, and teleported Kurse to Hel.
Kurse wreaked havoc in Hel looking for Malekith, who was not there, and Hela had Kurse driven into Asgard itself. There Kurse finally found Malekith, who had used his shape-changing powers to become a double for the Asgardian Balder. Kurse slew Malekith and then, his mission of vengeance finally fulfilled, he became peaceful and submissive. Later, Kurse aided Balder in the successful defense of Asgard during the attack of Utgard-Loki and the Frost Giants. Following this, Volstagg noted that Kurse was not a fit name for an Asgardian, and he was renamed Valgoth.