On a routine trip returning The Joker to Arkham Asylum, the Batman himself must deal with traps set within its inner sanctums, purposely set by the now escaped Joker, along with the rest of his rogues' gallery that are now free within the premises.
Take a proper look at the 'patient' photos plastered around the asylum walls and you'll notice a few familiar faces - they're actually members of the Rocksteady dev team. There's even a line of thug dialogue that name-drops art director David Hego directly, joking about his 'thing for blades.' Nice bit of self-insertion from the studio.
After you free Cash and Dr Kellerman from the laughing gas trap, look back through the glass into the room they were held in. Rocksteady snuck in a not-so-subtle nod to the much-maligned 1997 Batman & Robin film here, poking fun at one of the franchise's lowest points at the time.
In one of the game's twisted dream-sequence detours, Scarface delivers a version of Warden Sharp's usual welcome video, boasting that Killer Croc runs a security wing with a 'perfect record' and 'nothing but empty cells.' It's never spelled out directly, but the implication that Croc has simply been eating the patients is about as grim as this game gets.
Find Ra's al Ghul's body bag in the Arkham Mansion and it's there plain as day. Head back to the Morgue later on, though, and it's simply gone - no cutscene, no explanation, just a quiet little reminder that a man who's cheated death countless times in the comics probably isn't done yet.
