Letho formed an alliance with Iorveth and the Scoia'tael, enlisting their help in his plan to assassinate the Northern Kingdoms' kings. He validated his claim by presenting the head of the slain King Demavend III of Aedirn. However, Letho later attempted to betray Iorveth, leading to the death of his entire unit and the capture of one elf, Ciaran, by Flotsam's guards.