
This DLC adds two new Challenge Maps to Batman: Arkham Asylum, taking place in brand-new settings on Arkham Island. The "Insane Night" map pack features two fresh challenge maps. The "Totally Insane" combat map allows players to showcase their fighting abilities against waves of frenzied inmates from the asylum's archive area; the "Nocturnal Hunter" map tasks players with using Batman's tools and stealth tactics to ambush the Joker's henchmen from the dark.
Following the Joker's attack on Gotham City Hall, he is apprehended by Batman and transported to Arkham Asylum, where several members of the Joker's gang are temporarily held after a fire at Blackgate Prison. Suspecting the Joker intentionally turned himself in, Batman enters the asylum with him. The Joker's scheme unfolds as Harley Quinn takes over the security systems, allowing him to escape with the help of a corrupt guard who abducts Commissioner Gordon. The Joker warns that bombs placed throughout Gotham will detonate if anyone enters Arkham, compelling Batman to operate alone. Pursuing Quinn to the medical wing to save Gordon, Batman is exposed to Scarecrow's fear gas and experiences terrifying hallucinations, including visions of Gordon's death and the ghostly figures of his parents. After defeating Scarecrow, Batman captures Quinn and rescues Gordon. The Joker then leads Batman to Bane, who has been subjected to experiments by Arkham doctor Penelope Young. The Joker releases Bane, and Batman is forced into a brutal battle, during which Quinn manages to flee. Afterward, Batman retreats to a hidden Batcave installation on the island to replenish his equipment.
| PS3 | September 17, 2009 |
| X360 | September 17, 2009 |
| PC | September 17, 2009 |
| Mac | September 17, 2009 |