Lyra, astride Iorek, goes to an abandoned building the alethiometer pointed her toward. There, Lyra finds Billy Costa, who has been surgically separated from his dæmon. The Gobblers are experimenting on the kidnapped children using a procedure called "intercision." Lyra reunites Billy with Ma Costa, but the group is attacked by Samoyeds, who capture Lyra. Iorek and Lee follow her in Lee's airship. Lyra is taken to the bear king Ragnar Sturlusson. Knowing Iorek will be outnumbered, Lyra tricks Ragnar into fighting Iorek one-on-one. Ragnar, who usurped Iorek's throne, initially appears to be winning; Iorek feigns weakness and kills Ragnar, avenging his father and regaining his kingdom.