The Grim Knight

"The deadliest man alive. He's us if Joe Chill dropped the gun in the alley and we picked it up."

- The Batman Who Laughs talking about Grim Knight.

The Grim Knight is a major villain in The Batman Who Laughs miniseries of comics. He is a gun-obsessed version of Batman from the Dark Multiverse who is assisting The Batman Who Laughs with his criminal activities within Gotham City.

History
On an unspecific version of Earth in the Dark Multiverse, young Bruce Wayne's parents were shot and killed before his very eyes by the gun-toting mugger Joe Chill, who carelessly threw his gun to the ground while searching for Martha Wayne's pearl necklace. Bruce stood there in tears before noticing the gun and picked it up while Joe Chill told him to get lost. Vengeful, Bruce refuses to leave and fires the weapon at Chill as he tried to plead for his life.

Years later, Bruce had developed an obsession with using firearms and planned to use them with skills he had acquired from traveling the world to eradicate crime in Gotham City. However, Bruce felt just using these abilities was not enough when suddenly a giant bat flew through a nearby window, which Bruce shot dead and gave him the inspiration to become Batman. Bruce used his alter ego to begin a war of terror in Gotham, by first inviting the city's most wealthy and corrupt to Wayne Manor where he burned them all alive, before personally gunning down various crime lords and crime families that relied on the backing of those he killed at the manor.

Afterwards, Bruce used his family's company, Wayne Industries, to monitor Gotham City using a satellite and booby trap every piece of technology within the city limits (which he calls "colonizing") to turn Gotham itself into a weapon only he can wield. He also managed to do this with the aid of Mayor Harvey Dent, who caved into helping Batman when he irradiated one side of his face. Unlike other versions of the Dark Knight, this Batman never had a rogues gallery since he would kill his enemies after the first encounter. He even killed the Red Hood before the incident which would have created the Joker.

Eventually, Lieutenant James Gordon would attempt to trap and arrested Batman by having his men raid all the Dark Knight's arsenals hidden in Gotham and lure Batman himself to a rooftop where Gordon can capture him using a powerful magnet. Unfortunately, Bruce is one step ahead and kills Gordon's men on the rooftop by activating explosives in their bulletproof vests before shutting down the magnet he became stuck to. Batman attacks and holds Gordon over the building's edge to hear explosions from the arsenals the cops were raiding, then pulls him up to witness two GCPD blimps dive bombing into Arkham Asylum and Blackgate Penitentiary, killing everyone at those locations. Batman leaves the lieutenant tied up after claiming he will one day thank him for this sort of protection.

Six weeks later, Lieutenant Gordon has managed to stay under Batman's radar and deduces his secret identity. Gordon then gets help from the FBI and a confession from Alfred Pennyworth before confronting Bruce Wayne in front of Wayne Manor to finally arrest him for his crimes. At first Bruce plays innocent, but soon branches a gun after hearing the accusations against him. This time, the gun doesn’t do Bruce any good as Gordon snatches it away and knocks him to the ground defeated. Eventually, The Batman Who Laughs convinces Bruce to help him in his plans for Gotham City on Prime Earth as The Grim Knight.

The Batman Who Laughs Miniseries
Sometime after arriving on Prime Earth, The Grim Knight first appears at Arkham Asylum before two security guards who both mistaken him their world's Batman. One of the guards walked up to greet him but was immediately killed by the imposter before the villain proceeded to gun down waves of reinforcements using his own hefty arsenal. The Grim Knight soon came across Mr. Freeze's cell where Freeze commented on his behavior and tried to provide him with some helpful advice. However, The Grim Knight responded by blasting Freeze with a flamethrower before he made his way over to the Joker's cell and unlocked it. The Joker grinned as he asked The Grim Knight if he was here to kill him too. But the gunman denied this and stepped aside to allow The Batman Who Laughs to do the deed instead.

Later, it is reported that both villains killed almost everyone at the Arkham Asylum, although Mr. Freeze managed to survive The Grim Knight's attack while the person murdered by The Batman Who Laughs in Joker's cell was not the Joker, but an imposter. Batman (of Prime Earth) theorized that Laughs must of snuck The Grim Knight into their world during Barbatos' invasion of the DC multiverse and has been waiting for the right moment to use his talents.

Sometime later The Batman Who Laughs invades Wayne Tower and is confronted by his Prime Earth self who quickly grounds the villain in a fight. However, this was all part of Laughs’ plan as he gives The Grim Knight (on a nearby building) the signal to shoot his attacker with a bullet containing a Bat-Taser. As Prime Batman lies wounded on the floor, Laughs reveals to him that The Grim Knight is the result of Joe Chill dropping the gun on the night of the Waynes' murder and young Bruce picking it up. Years later, that Bruce would weaponize Wayne Enterprises and manufacture all sorts of lethal equipment to booby-trap the city with; becoming a deadly version of Batman who is at total war with his enemies. Laughs then proceeds to activate a special protocol designed to destroy Wayne Tower with a controlled implosion while mentioning that all other safety protocols that would of prevented the lose of innocence lives were disabled by The Grim Knight a couple of days prior.

After the destruction of Wayne Tower, The Grim Knight is sent to kidnap Commissioner Gordon as part of Laughs' plan to poison Gotham City. Arriving at his destination, The Grim Knight finds his Prime Earth counterpart with Gordon and barely misses shooting him unawares. Prime Batman quickly grabs his grapple gun and hooks The Grim Knight to a passing train, but the villain breaks free just as trucks block Batman's escape route. The Grim Knight reveals to Batman that back on his world, he has turned all of Gotham into his "Batcave" and rigged the entire city, from it's grid to it's vehicles, to serve as his "colony". He has even begun to "colonized" parts of Prime Earth's Gotham as well and tells Batman that either Gordon comes with him or an aeroplane flying above will drop from the sky then crash, killing everyone aboard. Batman complies and lets The Grim Knight take the commissioner before being warned that if he decides to follow them, there would be seventy two more booby-traps for him to deal with.