On a hunting mission for ender pearls, he and a few soldiers were ambushed by a group of Endwalkers, a cult who worship the End. He tried to fight but was hit by an axe enchanted by End magic. On the way to Elysium it is revealed that the axe was cursed and was slowing turning him into an Enderman.
Merek was contained in a sealed off section of Laergulon's tower to find out if the curse was contagious. Merek stayed there while the Elf wizards were trying to slow down and cure the curse's effects. Laergulon and Guldir eventually managed to stop the curse's progression, but not cure it.
Invasion of ElysiumEdit
During the Invasion of Elysium, Merek was not present in most of the battle due to the curse. However, when the Giants entered the battle of Finbar's side, Merek was forced to take action. Using the dark power of the End Magic, which had been corrupting him since his encounter with the End cultists, he was able to cast a spell and transported himself and the Giants to the End. There the End Magic became even more powerful and Merek was able to kill them. With no way back out of the End, it is presumed that Merek is still stuck there.