WARNING: The following article contains spoilers for the Justice League Dark story "Return to Caledonia" by Ram V, Xermanico, Romulo Fajardo Jr., Rob Leigh, Andrea Shea, and Alex R. Carr, featured in Justice League #59, available now.

In Justice League #59, the back-up story, "Return to Caledonia," focuses on John Constantine and Zatanna reuniting following the bloody war against the Otherkind and the Upside Down Man.

Unfortunately, as they try to figure out why a cult's on the rise in New Mexico, they discover the catalyst that gives rise to Future State's most demonic threat: Merlin.

RELATED: Justice League Dark: DC's Future Gives a Classic '90s Hero a CRUEL Death

In that story, the fabled mage from King Arthur's era returned and took the world by supernatural storm. Merlin seized all magic for himself, gathered an army of knights and began a genocide. It left the likes of Detective Chimp/Bobo, Ragman, Constantine and Zatanna on the run.

Now, we see how Merlin started this war, making his way to the Augustus Priory Ruins in Wales, where he honed his craft eons ago. This time, he's stronger than before, eliminating traps and going into the catacombs where he finds Excalibur after murdering the knight, Elnara, who spent an eternity protecting the legendary weapon.

After leaving the knight bleeding out in the pond, Merlin uses his dark magic to pull Excalibur from the rock. He then melts the sword and retrieve its gem before heading out to bring the mortal realm to its knees. Merlin no longer trusts humanity and believes this world must be purged, or at least controlled, which foreshadows his dictatorial regime in Future State.

RELATED: Justice League Dark Sacrifices DC's FIRST Magic Hero to Save Constantine

In "Future State," Jason Blood was revealed to be one of Merlin's greatest generals. While Constantine and Zatanna are investigating the case, Jason Blood appears. He comes bearing a message, warning them that reality is in danger, and while the members of Justice League Dark see him as an ally, little do they know that he may be destined to become Merlin's pawn.

With the smoke coming off him and a hint of reconditioning or amnesia, it seems this is when Merlin separated him from Etrigan and turned Jason into his war general, promising if Etrigan tried to attack, he'd murder Jason. Ironically, Etrigan bonded with Bobo in "Future State" and fought to find a way to save Jason, although this occurs after Merlin has already used Blood in his plot to disassemble Justice League Dark.

KEEP READING: Justice League Dark's Greatest Threat Just Stole Thanos' Best Line