The Batman: Arkham games were full of Easter eggs to decades of Batman media, with several references to the Dark Knight's infamous rogues gallery offering some of the series' most chilling moments. The world of Gotham is known for being one of the more horrific places in the DC universe and seems almost completely overridden with evil at the best of times, despite having heroes like Batman and the Bat Family protecting it.
Over Rocksteady's Batman: Arkham Asylum, Arkham City and Arkham Knight, and WB Games Montréal's Batman: Arkham Origins, players are invited to explore the immensely detailed locations outside of just the main story, more often than not due to trying to beat Riddler's trophy-filled Batman: Arkham missions. Through doing so, players can find themselves stumbling across teases for future titles, references to characters both old and new, chilling alternate endings to quests that can only be unlocked upon certain dates, and some of the creepiest Easter eggs that reference the horrors lurking among Gotham City.
Solomon Grundy's Nursery Rhyme Is Haunting In Batman: Arkham Knight
In order to solve Riddler's "He lives and dies in seven days, this beast you've tamed but his song still plays" challenge in Batman: Arkham Knight, players can uncover a secret room behind a fence that references the undead villain Solomon Grundy. This room holds a particularly creepy Easter egg, with a candlelit shrine to Grundy, whose "Wanted" poster hands on the wall as a haunting rendition of the Solomon Grundy nursery rhyme plays over a gramophone.
Grundy did appear in Batman: Arkham Origins Blackgate, Batman: Arkham City, and the latter's mobile spin-off game, Batman: Arkham City Lockdown, but was nowhere to be seen in Batman: Arkham Knight. He was referenced by Penguin, however, and scanning the Grundy shrine unlocked a Gotham City Story which revealed that Grundy was captured and ensnared within a Wayne Tech container until an overworked morgue attendant noticed a sound coming from it and discovered him. It’s implied that Grundy killed him and is on the loose somewhere in the city.
Scarecrow's Hidden Lairs Offer Chilling Secrets In Arkham Asylum & Arkham City
Scarecrow has several lairs to uncover across the Batman: Arkham titles. Once Harley Quinn's dropped the Intensive Treatment elevator in Batman: Arkham Asylum, players can find the first of Scarecrow's lairs, which reveals that he's been watching and studying Batman the entire time through a series of photos plastered on the walls above a map of the Asylum. Scarecrow was later dragged into the sewers by Killer Croc after subjecting Batman to a series of fear hallucinations. Although one of Arkham Asylum's multiple post-credits scenes teased his return by showing Scarecrow's needle-clad hand emerging out of Gotham's river and clutching a can of Titan, he didn't appear again until unleashing his "City of Fear" plans in Batman: Arkham Knight.
This version of the post-credit scene seems to be the canonical one in the rest of the series, as evident upon scanning his mask in Batman: Arkham City and finding a story about the villain managing to survive by holding onto a Titan box and floating ashore. One of the boats near Funland contains another hidden lair in which Scarecrow has been testing his fear gas on a thug strapped to a chair and has left several indications of his plans for Batman: Arkham Knight.
Batman: Arkham Asylum References A Horrific Murder
The horrific origin story of Arkham Asylum’s founder Amadeus Arkham and its first patient Martin "Mad Dog" Hawkins first played out in Grant Morrison and Dave McKean's psychedelic and haunting Arkham Asylum: A Serious House on Serious Earth graphic novel, and several references can be found around Batman: Arkham Asylum. Serial killer Hawkins murdered Arkham's wife Constance before sexually assaulting and decapitating his daughter, an act that drove Arkham over the edge and led to one of the locale's grizzliest-ever tales. On the anniversary of the murders, Arkham got his revenge by strapping Mad Dog to a table and electrocuting him.
A variation of Mad Dog's story was told via Batman: Arkham Asylum's "Chronicles of Arkham" tablets where a mind-controlled Quincy Sharp went through a psychotic episode and believed himself to be the reincarnated spirit of Amadeus Arkham. In this tale, Sharp claims that Martin was later deemed sane after years of direct treatment from Amadeus Arkham, but when his signature was required for his release, he used the pen he was given to murder Arkham's secretary. The chronicle's account implies that Mad Dog had acted out of instinct, and begged for forgiveness from Arkham, but after enduring so much from Hawkins, he gave up on him and killed him through electroshock therapy.
Mad Dog and Arkham’s history is referred to in two main Easter eggs in Batman: Arkham Asylum. A statue dedicated to Constance can be found in the Botanical Gardens, but it has been decapitated, with its head lying next to its plaque, which has "MAD DOG" scrawled across it. The bell in the Arkham Asylum's mansion also has an inscription saying "Arkham Asylum April 1 1922", referencing the day Arkham killed Hawkins.
The Court Of Owls' Presence Looms Over Batman: Arkham Origins
DC's New 52 comic continuity started in 2011, and with it came a new threat for Batman to face: The Court of Owls. Since their introduction, the shadowy organization has been revealed to be pulling the strings and controlling many of the city's major moves over the centuries, making The Court of Owls integral Gotham City villains, sending their Talon assassins to dispose of anyone who gets in their way. With the Arkhamverse prequel game Batman: Arkham Origins releasing shortly after the Court's comic debut, the group is referenced several times throughout the title's open world.
The first reference is on the balcony of the Royal Hotel, where statues that resemble Talons watch over the city. The second reference is a book featuring the ominous "Beware the Court of Owls" nursery rhyme, which can be found in the Gotham Bridge. While The Court of Owls never appeared in the Arkhamverse, they were a prominent part of a later project from Batman: Arkham Origins' developer WB Games Montréal: 2022's Gotham Knights.
Man-Bat Can Escape The GCPD In Batman: Arkham Knight
After a memorable jumpscare introduced Man-Bat in Batman: Arkham Knight, players unlocked the Creature of the Night side-quest and had to track down Kirk Langstrom's animalistic alter-ego across Gotham. After several encounters, Langstrom would be captured and handed into the GCPD, ending the quest. Returning to the GCPD on a certain date after completing Creature of the Night would result in a shocking discovery, however, as it will be revealed that Langstrom has escaped from his cell and is on the loose once more.
This was initially intended as an Easter egg for those who played on the Halloween of Batman: Arkham Knight's release year (but is still unlockable for those who change their PC or console date to October 31st, 2015) and doesn't pick up a new side quest to capture Man-Bat once more. Given how players don't encounter him again, this gives Batman: Arkham's Creature of the Night missions a rather bleak and ominous ending.