Leviathan is an organization founded by Talia al Ghul upon leaving her father Ra's al Ghul's League of Assassins. Leviathan's liturgy is staunchly anti-capitalist, and seeks to dismantle society and impose itself as the leaders of a new way. The organization has served as a threat to Batman Incorporated.
Leviathan first became known to the heroes of Earth as a terror group who kidnapped the child of a Yemeni shiekh. However, Batman suspected that something was up, and discovered that Leviathan was working with the shiekh, and was planning to attack the world with mind-controlled children and engineered metahumans.
Batman immediately connected the organization to an apocalyptic vision he'd received while coming back from the dead, and positioned his Batman Incorporated organization to oppose them. After some moves, Leviathan seemed to form up behind Doctor Dedalus, a Nazi masterspy imprisoned on the Falkland Islands, with a predicted lifespan of months due to Alzheimers'. In the aftermath of Dedalus' breakout, further investigation showed that a paper-trail showed a flow of child soldiers from training camps in the central African republic of Mtamba to locations around the world, for use by Leviathan in their campaign.
Leviathan's goals seemed to include the subjugation of poor communities using drugs. In Batman Inc's struggle against Doctor Dedalus' master plan, they struck, and hit empty locations, which were in fact pre-prepared traps by Leviathan. Recovering, they realized that Dedalus was a feint, designed to make them show their hand on the eve of the war. Via a telephone, the leader of Leviathan, Talia al Ghul, spoke from their new headquarters opposite the cinema on Park Row. Talia stated Leviathan's goal was war with Batman's followers and the destruction of civilization.
Later, Talia took control of the League of Assassins and added its agents to the plan. The plan began by seeding mind-control chemicals in the Gotham food supply through the "Dark Tower" fast food chain, while taking control of the Brothers Grimm Syndicate, which controlled the club on Gotham's West Side. Using a combination of agents in the school system, the police, and the civil service, Leviathan worked to control Gotham's children.
Five years ago, Talia ordered her most trusted assassin to kill one of Leviathan's underbosses, who had the intention to reveal the existence of the organization to the U.S. authorities. Trust inside the criminal network was shattered and when Talia died and then was resurrected, she was ousted from her position as leader of Leviathan. The organization then fractured into various factions, led by competing leaders. The impact of the civil war was so great that independent assassins such as Deathstroke deemed it necessary to step in and force a resolution to the conflict.
Mark Shaw eventually acquired control of the organization and offered Talia a partnership alongside him. She instead decided to kidnap Clark Kent so Superman will come after them and help take the organization down. Shaw however had already been aware of her plan and freed him from the Kryptonite belt around his waist. Firestorm and Dex-Starr later attack Leviathan soldiers after freeing him with Lois Lane and Jimmy Olsen. Shaw later threw out Talia from his ship for trying to go against him, but Superman and the other heroes couldn't discover the new leader's identity.
Shaw then proceeded to take out all the other shadow organizations such as D.E.O, A.R.G.U.S, Checkmate, and Spyral. While many assumed he had killed the agents of the organizations, in actuality many had been brainwashed or persuaded into joining while Leviathan had also appropriated their technology. They also nearly assassinated Sam Lane and Amanda Waller after they refused to join but their actions caused a team of detectives and Lois to go after him.
After Superman confronted them in Cuba while tracking Waller, he was drained by an energy matrix attack. Lois organized another team to go after him. Leviathan meanwhile had Superman transported to their location in Chicago and tried to convince him to join him, revealing how Spyral had developed technology to take his son Jon down and promised to fix the "broken world". Shaw then revealed that he took out the spy organizations to end all secrecy and revealed his true identity to him. He also promises to end all secrecy by exposing all secrets of the world's governments.
The detectives and Talia however track down Mark with the help of the source signal of Kate Spencer's Manhunter staff. Talia's presence also made some of her former followers unsure at standing by Shaw's side. Leviathan members escaped but their plans of revealing every secret was foiled as Batgirl, who had pretended to join their organization, had stolen their hard drive containing them. They had however suceeded in killing Sam, as Zatanna was forced to teleport him when they tried to bomb him.
Before Shaw could make his next move however, Lois exposed his identity with the help of Clark, causing him to rethink his plans. Shaw then agreed to start a destructive campaign against the superheroes after his followers demanded it.
Leviathan later pretended to ally with Legion of Doom in battling Superman and the Justice League. Shaw stated to Lex Luthor that Lois only revealed his identity because he wanted her to while also showing him their headquarters, a floating island filled with lodgings for Leviathan members. During the fight with League however, they would betray the Legion since Shaw thought that people like Lex were the reason the world was broken. Shaw teleported the Legion away to a far off place instead of attacking the League.
After the fight in Metropolis, Shaw berated his people for Amanda Waller getting her hands on their technology and punished Dr. Netz for being behind it. The organization then proceeded to buy out Markovia and Shaw appealed to everyone live to help them fix the world.
Leader:
Leviathan
Members:
Quietus
Aftermarket
Guardian
Hangman
Jonah Nine
Wishbone
Son of Pyg
Allies:
The Legion of Doom
Former Members:
Talia al Ghul
The Heretic
Doctor Dedalus
Dr. Netz
Lord Death-Man
El Sombrero
Scorpiana
Miss Hexley
Batgirl
Bloodvessel
Breacher
Casey Klebba
Cradle
Eliza Danvers
Endgame
Guile
Gunn
Grave
Killbox
Raze
Mr. Remedy
Rutger Orestes
The Silencer
Zygo
Goatboy
Absorbed League of Assassins Members:
Dark Archer
Detonator
Iron Aron Abromowitz
Hook
Kitty Kumbata
Maduvu
Mad Dog
Professor Ojo
Razorburn
Shellcase
Shrike
Sin Tzu
Sportsmaster
Whip
