Boreas said Icaronix belongs to a faction that opposes the Shadow Elders. He must be unmasked and destroyed. You met Gaix and then Finn to learn that Icaronix is a member of the Lepharist Revolutionaries and currently hiding in Azoturan Fortress, a bind point built by the Lepharists in the Abyss. You went to Azoturan and met with spies of the Shadow Elders who helped you locate Icaronix. When he appeared, you pursued and killed him. When you returned to Reshanta and told Yuditio what happened, he thanked you and asked you to pay close attention to the Lepharist Revolutionaries from now on.