A 2009 video game based on the Batman franchise, and the first game in the Batman: Arkham series. The game is loosely inspired by Grant Morrison's Arkham Asylum: A Serious House on Serious Earth and Dan Slott's Arkham Asylum: Living Hell. It features some of the talent behind Batman The Animated Series, including a storyline by series writer Paul Dini and voice actors Kevin Conroy, Arleen Sorkin, and Mark Hamill reprising their respective roles as Batman, Harley Quinn, and The Joker.Gotham City is just beginning to emerge from another chaotic month. First, Blackgate Penitentiary is destroyed in a suspicious fire, forcing the Gotham police to move its inmates to Arkham Asylum; then the Joker goes on another crime spree, culminating in a failed attempt to kill the city's mayor. The game opens with Batman ending the Joker's rampage and bringing him back to Arkham, where Warden Quincy Sharp hopes the clown will finally be rehabilitated. What they don't realize is that this time, Joker actually wants to be at Arkham: after escaping from the guards, he and Harley Quinn break into the asylum's security, free the inmates, and seize control of Arkham Island. Realizing that his archnemesis is up to something far more sinister than a mere breakout, Batman fights his way through the waves of convicts and tries to find out what the Joker really wants with the asylum.Notable for being extremely hyped up by various outlets and still being released to critical acclaim, breaking the stigma that has been plaguing DC Comics games before, and winning a Guinness World Record for "Most Critically Acclaimed Superhero Game Ever".The actual gameplay is divided into several modes: straight combat, striking from the shadows and detective mode, with some platforming elements tying the whole lot together. Each is well designed and suitably immerses you into the world and abilities of the Dark Knight. On the story and characterization side, it is filled with an appreciation for the comics' mythology (the creators of the game stated that they drew inspiration from every facet of the Batman mythos rather than concentrating on a single version/interpretation), and utilizes many of Batman's greatest foes to their fullest. And despite an initial glance, the game is certainly not kid-oriented; it has some serious scary elements (especially in the case of Scarecrow) and vicious action sequences.A sequel - Batman Arkham City - was released in 2011.A prequel game titled Batman: Arkham Origins, and a portable spinoff/sequel to said prequel titled Batman: Arkham Origins Blackgate, were announced on April 9, 2013, and are scheduled for release on October 25 of the same year. Warner Bros. Games Montreal will be developing the main game, instead of Rocksteady, and Armaturenote A relatively new studio founded by former Metroid Prime staff will be developing the portable game.Has a Character Sheet.
This game contains examples of:
Abandoned Hospital: The Medical Building. Second only, maybe, to the Penitentiary as creepiest building ever. Broken tiles, flickering lightbulbs, doctors held hostage, eerie silences, gurneys and whole rooms sitting empty—as if life just up and vanished out of the whole building. Oh, then there's what who you find in the basement. Then the morgue. Then the Scarecrow gets really clever...
You find a tape containing an interview with the Riddler, where he comments on how his dad called him a "moron" over and over again. To prove him wrong, Edward entered a contest at school, where if he solves a nearly impossible logic problem, he gets $20. He won, but his dad demanded him to confess that he cheated. He denied it only to get hit. He actually did cheat.
If you unlock Humpty Dumpty's profile, it will say that when he was a child, his parents died as part of his decades-long streak of horrifying, almost supernaturally bad luck, leaving him to be raised by his abusive grandmother. What Humpty Dumpty did to his grandmother after years and years of abuse wasn't pretty at all.
Action Commands: When enemies are about to strike, an icon appears over the head indicating that you can press a button to Counter Attack — whether or not you're already in the middle of a combo. These icons are disabled in Hard mode.
You also get to use Action Commands to make automatic takedowns, both of the stealthy and non-stealthy variety.
Adaptation Distillation: Truly one of the greatest incarnations of the Dark Knight and his rogues ever. It's actually a potluck of the best aspects of practically all his previous media incarnations: the grittiness of the Christopher Nolanmovies, the gothic architecture and film noir-ish mood of the Tim Burton films, the canon of the comics, the voices and writing talent of the animated series... It's difficult to imagine an incarnation of the Dark Knight that could so easily please all of Batman's fans from any medium.
Batman is primarily based on his comic version, but he has the voice of the animated version and his suit actually looks like body armor with a glider cape.
Joker — again, primarily based on his comic version, but he wears a suit that looks custom-made and the red of his lips extends a good deal past the corners of his mouth and onto his cheeks much like in The Dark Knight, he has a face that looks a lot like Jack Nicholson, he transforms into a muscle-bound hulk similar to Kevin Michael Richardson's Joker, they used Mark Hamill's voiceand we can count Hamill's voice as a Caesar Romero reference. There's a lot of similarity there, especially in the laugh, thus completing the full spectrum of Batman Jokers.
The Clayface in this game bears Basil Karlo's name (blink-and-you-miss-it when Bats takes Harley's "party list") and now-in-continuity powers: otherwise he's an amalgamated Batman: The Animated Series Clayface (Matt Hagen) and Preston Payne.
After Combat Recovery: Achieved in a somewhat roundabout way. Gaining experience points restores your health, and beating people up gives you XP. Ergo, damage taken in combat may be healed from the XP you got from fighting. Depending on how much damage you took and how much XP you got, you may or may not be restored to full health. Bosses reliably give you enough XP to heal fully, however.
The reason this works for this trope is that the XP doesn't tally (and thereby the healing doesn't begin) until you finish the entire encounter, whether it's a gang of ten mooks trying to beat you down or a room full of gun-toting mooks in a stealth segment.
Air Vent Passageway: Vital gameplay mechanic, and arguably the only reason Batman wins. Although, as Joker mentions to a henchman in your first trip into the sewer, he can't take every detail into account for something as big as an island takeover.
All There in the Manual: The Road to Arkham comic that comes with the game reveals a few specific details about the events beforehand. One example (if you missed it in the game itself) is that Dr. Sarah Cassidy survived having Zsasz pay her a house call, as she was rescued by Batman at the last second.
Averted with Dr. Sarah Cassidy. Although Zsasz escapes and goes after her, and though he makes it to her apartment, where he knocks on the door and she answers, she still survives. Thank you, Batman, and your propensity for big damn hero moments.
Also inverted with Scarecrow's interviews. The fourth ends with him having apparently won, and leaving you wondering how it could possibly get worse than this. The answer: it doesn't. The fifth has Batman ruining his plans. Effectively, an apocalyptic log for the villain.
Arbitrary Skepticism: One of the doctors admits before being saved by Batman she believed he didn't exist.
According to Dr. Gretchen Whistler, it's perfectly acceptable that Killer Croc is an eleven-foot tall, reptilian man-beast, but the idea that he'd actually eat people is absurd.
Joker: (about the Batmobile) Every thug, villain, murderer, and kindergarten teacher that isn't carrying out party orders should head there now and smash it to pieces!
Joker: What do you really fear, Bats? Failing to save this cesspool of a city? Not finding the commissioner in time? Me, in a thong? (maniacal laughter)
Oracle: Let's see, random threats to her family, a couple bad jokes, a picture of a dead baby, and a threat. He says, "I'm coming for you! I want what I paid for!" And then another joke about wheelchairs, lovely... and a drawing of some kind of donkey.
A lot of the "attack" animation results are pretty over the top, even for a 210-pound man of pure muscle.
In the final scene, where Batman puts explosive gel on his knuckles and punches Joker - at the very least, his arm should be broken.
Possibly justified, as by the end of the game, Batman's wearing a suit of cutting edge armor; theoretically, it could absorb or deflect the force of the explosion. Batman was injured slightly by the punch, as he was holding his arm as if it was hurt.
Awesome Yet Practical: Detective Mode, oddly enough. A default ability to pinpoint and number thugs, identify what they're armed with, isolate forensic trails and Riddler trophies, all to be used with no restrictions except for using the code breaker; it's digital clairvoyance.
The main problem is that there's no reason to ever turn it off, making the game significantly uglier until you go blind from sensory overload and try to punch a mook on the other side of a wall.
Ax Crazy: This being Arkham Asylum, there's a lot of them about.
Zsasz. There's a reason he doesn't show up in the animated shows.
The author of the "Spirit of Arkham" carvings hidden around the island, a.k.a. Warden Sharp.
The Riddler's Patient Interview tapes show him to be a very scary person.
Bad Boss: Joker clearly doesn't care what happens to his minions. He often goes over the Asylum's loudspeakers to denigrate, threaten and just scare them.
"If you don't find him, I just might expose you to some of my happy gas. Actually, I think I'll do that anyway. It sounds fun."
"Come on! He's just one man! One man dressed like a lunatic and armed to the teeth. Go get 'im!"
"Hey Bats, go easy on 'em. For me? Ah hell, what do I care! DO YOUR WORST!"
"Batman, I know you can hear me. I want you to hurt these guys. They mean nothing to me."
"Don't worry. Rumours that Batman drinks human blood are compleatly unsubstantiated"
"Batman murdered fifteen of my crew. Tore their heads off and ate their hearts. I know, what an animal!"
"Don't be afraid of him! He's just one guy! Probably not even human!"
Harley either for that matter. Before the final battle he mentions how slapping Harley around is his "hobby".
Then he leaves her locked in an Arkham cell, even though she is convinced he will eventually let her out when the time is right. He doesn't.
Early on, there is a criminal speaking to Joker over a live feed. Batman can walk right up behind him and take him out, or just stand there listening to Joker threatening the poor guy's family. After he's been dealt with, the green-haired madman addresses Bats directly, commenting that he could warn his henchmen ahead of time, but that this way is more fun.
Later on, he "rewards" a henchman's failure to find you by promising him he'll send someone over to break his wife's legs and when the poor man protests, Joker asks the guys if he doesn't think he's being treated generously.
This needs to be expanded on. He really IS being generous by this, made clear by his "joke" after.
"Did I ever tell you the one about the guy who came home to find his wife a parapalegic?"
While you're busy taking out armed thugs from the shadows one by one, the Joker starts openly rooting for you while the remaining henchmen get more and more terrified.
"Aren't you guys wondering which one of you he'll take out next. I know I am."
Not that the mooks aren't equally bad. Joker asks one guy to kill his sister in order to gain entry into his gang. He does so... and claims he "never liked that bitch anyway". The other mook replies Joker gave him the same order, but he didn't have a sister, so he killed some random woman. Joker approved.
With Selective Re-Education, you can bring home the loved one that you always wanted.
It ended up becoming a prison when The Joker burned Black Gate prison, forcing Gotham PD to transfer its inmates to Arkham.
Benevolent Architecture: Arkham features hundreds of grapple-worthy gargoyles inside the buildings. Handwaved by revealing that Bruce Wayne donated the things. During the stealth portions of the games, some of the Mookswill comment on this. The Joker later figures this out and orders his mooks to booby trap the gargoyles... in one room. After that, no one thinks to do it again.
Perhaps some Fridge Brilliance here, in that the Joker knows that blowing up gargoyles wouldn't be a trick that worked after Batman figured it out. Of course, Joker is completely insane, so he could just be happy watching Batman pummel his mooks, and not really care to keep them safe.
Big Damn Heroes: Being Batman, you get to do this several times during the game.
Big "NO!": Batman does this when taking a dart for Gordon.
Joker-Bane when he is defeated. Hilarious when you realize who is doing his voice.
Black Comedy: The Riddler's take on the ancient riddle of the Sphinx. Child-diddle-riddle.
Dr. Young: How can you joke about something like that? Riddler: Easily, doctor... it's not my baby.
Blofeld Ploy: Played with in a scene where Batman is confronting the Joker and two mooks; the Joker points a gun at Batman, then shoots the two mooks instead, because the gun is actually loaded with the performance-enhancing Titan formula.
Bloodless Carnage: The game is only rated TEEN because of this. Otherwise, it is bone crunching violence (although when Batman is actually snapping bones, the camera always swings around behind him so you don't see it happen).
No matter how much you beat up a particular mook - yank the floor out under his feet, knock him off a ledge, or just plain breaking his bones in until he stops moving - Detective Mode will always list them as 'Unconscious', and they will never, ever, wake up again.
Body Horror: Titan induced transformations are a real freakshow. They cause a person to grow in size, with bone spikes protruding out of their flesh, notably with spikes on their spines. Titan Joker is even worse with larger back spikes, large claws, protruding ribs, and areas of his skin torn open, showing muscle tissue.
Joker: (after choking a security guard to death with his handcuffs and knocking one of the medics out upon being freed from his handcuffs) "The choke's on you!"
Additionally, most major villains have a few variants to deliver in the Mission Failed screen, with Joker providing most of them.
Bond Villain Stupidity: Repeatedly. Batman even does a heroic version first when, knowing Batman absolutely refuses to kill, Joker taunts him by openly giving him a free Batarang shot that would knock Joker over a ledge to his death; for a moment, Batman looks tempted to take it, but he then woefully backs down. A lot of guards and staff would have been saved if you had thrown that Batarang, Batsy.
After that, Joker gets multiple opportunities to cleanly kill a helpless Batman throughout the game, but declines to do so until Batman truly becomes a thorn in his side later in the game.
At one point, Joker even goes so far as to demonstrate that he could kill you easily by blowing the brakes on the elevator in which he trapped you. He decides it wouldn't be fun.
Scarecrow: "You married your wife because you were scared of dying alone. You had children because you're scared you won't leave behind anything important. You go to doctors because you're scared of dying... need I go on?"
The Joker subjects Batman to one every time he enters the Visitor's Room before the finale.
Batman gives a great one to Scarecrow in his last interview tape:
Batman: You failed, Crane. Again. I've been working with Dr. Kellerman, creating an antidote to the toxins in your cologne. He fooled you, Crane. How does that make you feel? Threatened, humiliated? ... Scared?
Brick Joke: When Joker first has control over the asylum, he taunts Batman, saying "You were expecting maybe Two-Face?" The ending cutscene has Batman overhear police reporting that Two-Face has just robbed a bank.
When the Riddler first contacts you, a pop up appears stating that the call is being traced. Once you complete all the Riddler challenges, Batman reveals that he forwarded the location to the police, and they're right outside Riddler's door.
Broken Bridge: You will not be able to walk straight to anywhere. There will always be a locked door or something blocking your path, forcing you to take the long way around.
Bullfight Boss: Bane and the Titan-augmented goons. Unusually for this trope, they are smart enough to stop before hitting a wall, unless you hit them in the face with a well-timed Batarang.
But they aren't smart enough to avoid hitting each other, making it possible to beat the second-to-last-fight without actively fighting. Just line up the empowered henchmen so they'll run into each other and bowl over the smaller henchmen and focus on dodging and bataranging them in the face when they charge.
Butt Monkey: Due to his Bad Boss tendencies, Joker ends up leaving two henchmen stranded above a cloud of Smilex and detonates some explosives before the henchman placing them gets clear. All three incidents name the henchman as Razor. Either this guy really has bad luck, or Razor is a very common street name in Gotham and Joker is actively working to make it less common.
His luck doesn't improve in the sequel. In Arkham City, you can learn that he quit Joker's gang, probably due to the events listed, and joined up with the Penguin. Who dropped him in a pool of boiling water and razor blades.
One of the very first things you notice is Frank Boles's hip flask. It is nearly impossible to play without seeing it. Sure enough, it turns out to be a means to track him.
Joker's comment to Boles about keeping his mouth shut or else it'll get him into trouble. You track Boles by the bourbon, which he drank from the flask, in his breath.
Every grate, weak floor, and force field you come across but can't open until you have the right gadget.
In The Stinger, one of the villains you previously dealt with but did not detain - Scarecrow, Bane or Killer Croc - reaches up to grab the Titan formula.
Closed Circle: Joker threatens to blow up parts of Gotham if anyone else is seen going near Arkham, leaving Batman all alone (though at least one bomb is a fake). Subverted when Batman calls in his personal jet, showing that he could leave the island any time he feels like it, but isn't about to leave Joker and Co. running the Asylum. The threat is sufficient to keep any other superheroes out of the picture, because it doesn't matter how powerful they are, if Joker sees them and detonates the bombs.
A particularly neat effect is the stubble Batsy grows over the night. Quite a lot, in fact. What a man!
Clothing Damage occurs in the combat challenges as you take damage. However, the trope is averted if you use the armored batsuit.
It oddly becomes paradoxical, where if you clear the stage with your recovered health, your suit magically regenerates as well. Also, the costume doesn't become damaged until the end of the round, where a very visible model skip occurs.
Collapsing Lair: The rooms where you fight Bane and Poison Ivy. In Bane's case this is justified as he damaged the supports during his fight with you. Ivy is at least a handwave because the giant plant she used came up through the floor.
Combat Pragmatist: Batman's fighting style in a nutshell. You're even encouraged in the combat challenges to throw thugs into force fields, into their friends, and bottomless pits.
He does wrestling-style submission moves for the express purpose of breaking bones.
The Computer Is a Cheating Bastard: Both frustrating and frightening is the point after Joker releases all the lunatics in the penitentiary. There are multiple occasions throughout the game of these lunatics popping up out of absolutely nowhere without showing up on Batman's detective vision even when they might be right next to lunatics that Batman can see.
Conservation of Ninjutsu: Since the combat system encourages Batman to switch targets constantly to maintain his combo streak, the fights actually get easier when he is up against massive odds, as opposed to a small pack.
Contest Winner Cameo: The winner of a contest got both their face and name in small parts of the game - their face was used for the inmate near Clayface's cell, and their name was on the party list.
Continuity Nod: Despite being in its own continuity, there are artifacts and other references to both famous and obscure Batman villains, indicating that the major stories of Batman's history also occur in this continuity in some form. As well, display cases can be found holding the belongings of various villains who don't actually make an appearance, from Catwoman's gloves and goggles, Penguins trick umbrellas and the actual Scarface puppet.
As well as more than a few commentary from the villains, Bane for instance who references how he once 'broke' Batman, which did happen in the comics in his first appearance.
Joker too considering the level of planning he used to take over the Asylum.
The cutscene after the fight with Bane. Bats crawls out of the rubble and plays with his gauntlet, then chats a bit with Gordon. Then Bane comes crashing through the rubble, threatens to break the Bat... and gets creamed by the Batmobile. Crazy-Prepared.
The Riddler must be this as well. He left his trophies everywhere, including places that you need special gear and Batman-like athleticism to reach. And he knew exactly where your journey would take you across the island.
There's also Killer Croc's lair, in which we get to see the preparation: Right when entering, Batman both puts a sonic batarang on a pipe (to help find his way back, which is understandable) and sprays a large bat shape with his explosive gel on a piece of unstable floor - which he refuses to detonate if commanded to. Fastforward a few minutes and when he's chased out of the lair by the Croc...
A significant occupational hazard for any doctor who interviews Arkham's crazies. Victims include Dr. Harleen Quinzel aka Harley Quinn, the doctors in charge of interviewing Scarecrow and Poison Ivy, and Warden Sharp.
A particular example is Dr. Young's psychoanalysis of Batman, as detailed from bonus material in the collector's edition. She attributes Batman's "multiple disorders" to genetic predisposition and substance abuse. It doesn't help she's getting her info from the inmates themselves.
Dangerously Genre Savvy: The Joker. He's following Batman every step of the way. Those "present boxes" you keep finding? Left by him as a way of congratulating you for jumping through yet another of his hoops. He mentions at least once that he could blow the brakes in the elevator Batman's in if he felt like it (and in fact, he has Harley do just that to slow him down in the "Intensive Treatment" facility).
He knows his mooks don't have a chance. They're just there to slow Batman down and to amuse the Joker. He even makes fun of them as Batman takes them out.
Once in the story mode and in all of the "extreme" stealth challenge modes Joker rigs up those gargoyles Batman loves so much with proximity explosives. That'll teach you to hide in the rafters...
Darker and Edgier: The game's tone is essentially an R-rated version of Batman: The Animated Series, mixed with influence from Grant Morrison's A Serious House on Serious Earth, the miniseries Arkham Asylum: Living Hell, and some Christopher Nolan films. The Riddler, for example, has never been as bloodthirsty (see below) as he is in this game. In fact, the only reason this game wasn't rated M is because there's no blood or gore.
Deadly Gas: Joker's green laughing gas, and red toxins from Ivy's plants flood several areas.
Defiant to the End: If you notify a mook to your presences when Harley is holding Gordon. Before she kills him, he simply says "Do your worst".
Demoted to Extra: Borderline example: Zsasz is little more than a "tutorial boss," you only face him twice, and he goes down in one hit both times. That said, there is evidence of his handiwork in other places, such as various corpses of guards he's posed in lifelike situations.
Determinator: Batman is not going to let the army of mooks, released supercriminals, or multiple large doses of fear toxins get in the way.
How does Batman shrug off knife wounds, gun shots, tasings, fear toxin, mutant plants, being thrown through bricks walls and taking on dozens of burly brawlers at once? He punches people. Batman restores health by punching people. For the Bat, punching people heals bullet wounds.
Batman: Barbara, listen to me. Joker will not win. I won't let him.
Deus ex Machina: In the same manner as the original Greek plays; Batman needs to cross a large gap. No problem, a few button presses and the Batjet comes down from the heavens and bestows upon him the appropriate device. It's a Chekhov's Gun, as a Batplane can be seen in the secondary Batcave when you first enter it.
Much less explained is at the end of the game, when Joker shoots Batman with the Titan toxin. Despite the fact that it's a chemical formula that operates completely on biological processes, Batman doesn't change into a monster through sheer force of will. Sure, he's the goddamn Batman, but that's still stretching belief. It was awesome, though.
Though it seems he merely delays it a little; eventually he is forced to use the last of the antidote on himself, meaning he has no way to de-power Joker.
In addition, none of the Joker's henchmen have shoes. Even in one brief encounter when they're disguised as guards they continue going barefoot, allowing keen-eyed players to avoid walking into an ambush.
Does This Remind You of Anything?: If Batman visits the patient center after beating the bosses prior to beating Poison Ivy, he'll talk to Joker about his sessions and his current state of mind in a manner similar to a Psychologist/Psychiatrist with Batman being the patient.
Door To Before: Several places in the game, the tunnel at the end of a section ends up on ledge overlooking somewhere Batman was earlier, providing a shortcut back. (The ledge is always too high up to get to from the other direction.)
Down the Drain: The sewers under Arkham, especially Killer Croc's lair.
Dream Team: The combination of elements picked from previous incarnations of the series. See Adaptation Distillation above. And for a more straightforward version, the number of classic characters, especially villains, present in the game.
Dutch Angle: When Scarecrow's fear toxin starts to set in, the camera starts tilting ever so slightly as you move, until it's at a significant angle.
Dynamic Loading: The larger outdoor areas are divided by simpler corridors, doors could open faster or slower depending on how much loading is left to be done for the room on the other side, and in the worst case if Bats runs fast enough in some places he'll outright stall for a second while the game halts to catch back up. He's also forcibly slowed to a stoic walk whenever receiving a radio conversation.
The site includes information about the asylum, its inmates, and secret details about the game's plot that you might not otherwise have grasped... for those with the right login...
This game had one of the most well hidden easter eggs in recent gaming history. A secret room in the Warden's office that didn't show on the map and that you had to place three layers of explosive gel in very specific spots on the wall to blast open. It showed plans for Arkham City. It was so well hidden that it took months before Rocksteady revealed it.
The high-security inmates (the knife guys) can block strikes as long as they aren't stunned, and the mooks with stun batons will zap you if you hit them from the front. Both also have unblockable moves.
The ones with the guns are worse. The others you can just flip over and attack from behind. If they have a gun, you have to sneak up on them or drop them with batarangs. However, they won't fire into crowds — a fact Batman can take advantage of by making sure the other mooks you're fighting are between you and the gunner. As well, you can chain melee attacks towards them in the process.
Endless Game: The Totally Insane downloadable map pits Batman against an endless army of Mooks to see how long he'll last - or how big a score he can rack up until his inevitable defeat.
Enemy Chatter: One of the most fun parts of the game is listening to the Mooks freaking out after you encounter them. If you listen to their conversations before you start on them, a lot of conversations delve into Even Evil Has Standards after getting the batclaw. It varies from some henchmen being less than thrilled about their friends' past exploits, getting fed up with the antics of the super villains, and one case of Even Bad Men Love Their Mamas.
Some of these even wander into Easter Egg territory, as there are a few bits that you'll only hear if you hang around a certain area, sometimes after doing appropriate actions.
Enemy Detecting Radar: Detective Mode lets you see the glowing X-ray skeletons of people through walls; during sneaking sections this is vital. In a few cases this can be used to spoil the surprise of an inmate hiding in a box to ambush you.
Entertainingly Wrong: Listening to one of the Riddler patient tapes reveals that the Riddler is convinced that Batman is a criminal like him who steals from the criminals he apprehends to fund his operations and has bribed Commissioner Gordon to gain the police's compliance with his actions, because he's convinced that "no one is that selfless". Considering Batman's actual secret identity, it's yet more proof that the Riddler isn't quite as clever as he likes to think he is.
Also an instance of Even Evil Has Standards: Shortly after Joker releases the lunatics, one of the Blackgate Joker henchmen openly questions why Joker would do something like that. Unlike the above example, the other mooks don't hush him or mock him for saying this, implying that they agree with him.
Everybody's Dead, Dave: Early in the game, you can find holdouts of Arkham Security or medical staff all over the island. Batman saves them from whatever peril and tells them to stay put where it's safe. This almost never works, Batman finds them dead on his next trip through the area. By the end of the game Gordon, Cash, Sharp, Batman and a handful of guards and doctors look to be the only survivors of the nights' events.
Everything Sensor: Detective mode, see enemies though walls, tell you if they have guns or not, isolate DNA and chemical traces, track finger prints of a certain age, identify weak walls, grapple surfaces, control boxes and air vent covers, detect shapeshifting clay monsters.
Evil Laugh: Joker, Scarecrow, Poison Ivy, the Riddler, Killer Croc, hell, even Commissioner Gordon gets one! Sort of.
Explosive Instrumentation: The control panels that Batman tampers with tend to blow up after being compromised instead of, say, just shutting down. Perhaps this was meant to take down hackers but Bats has a fancy device that lets him work from a safe distance.
Falling Chandelier of Doom: There's a big impressive chandelier in the asylum's library, which inevitably gets dropped. Likewise the bell in the clock tower.
Flash of Pain: When Batman takes damage, the screen goes black and white and gets significantly darker for a moment.
Flunky Boss: Most of the boss battles are structured like this. The actual bosses only take a handful of Action Commands to KO but in between each sequence they get hordes of Mooks to screen for them. Despite being heavily used, this works quite well.
Follow the Leader: The Captain America: Super Soldier game copies this game's basic fighting engine (though not quite as well), with a counter, dodge, stun, and attack button. It also tries to copy the Metroidvania style layout, but to less success. Still, imitation is the sincerest form of flattery...
Foot Focus: Poison Ivy, where, when she walks away from just being released, the camera will focus on her bare feet as she leaves.
Foregone Conclusion: Dr. Sarah Cassidy spends the first two Zsasz tapes interviewing him, only for him to develop an unhealthy fixation on her and be transferred to another doctor's care. In the last tape, Zsasz is right outside Cassidy's door, waiting for her to answer the door...but she's one of the doctors Batman rescues in the Medical Center early on, so everything turned out alright.
Foreshadowing: Many characters who are never seen, but leave traces of themselves behind as Riddles, go on to have major roles in the sequel. For example, the player can find Catwoman's whip and goggles on display in a glass case, Mr. Freeze's, Two-Face's and Clayface's cells, a series of case files written by Hugo Strange, and a duty schedule that lists Dr. Thomas "Hush" Elliot" as an employee. Ra's al-Ghul's corpse even shows up in the morgue, only to vanish when the player returns.
For the game itself, at one point, a security guard angrily tells Joker as he's being taken back to Arkham that he'll pay for the deaths of three of his friends from the previous escape, only for Joker to be shocked that he only managed to kill three, and state that he'll try to improve by killing 100 more people the next time he escapes. By the time of the end of the game, he pretty much did kill well over 100 people at Arkham.
The Fourth Wall Will Not Protect You: At the third encounter with Scarecrow, the entire game seems to crash. It's actually the fear toxin who plays on the player's fear: the console/PC crashing or freezing.
Game Engine: Uses the same Unreal 3 engine that powered Gears of War, which is easy enough to tell once you learn that information.
Game Over Man: If you get killed as Batman, you get Joker (for failing on his or Zsasz's segments), Harley Quinn, Bane, Scarecrow, Poison Ivy or Killer Croc, depending on how you died. If you get killed as Joker, it's either Aaron Cash or Batman himself.
Genre Busting: It's a bit hard to classify, having elements from stealth, beat-'em-up, RPG, survival horror, and Metroidvania games.
Genre Savvy: Batman (duh) throughout the whole game, beginning when he senses something wrong with Joker's easy capture. Turns out Joker is even moreso, having counted on Bats sensing something wrong so he would come along and be trapped on the island. As for how savvy Bats is—as soon as Joker punches the very first guard, Batman shouts something along the lines of "Joker's escaped!". Not "Joker needs to be restrained!" or anything that implies the Joker's just being uppity, but rather a statement that Joker's -already- out of control. Also, when the lights go out while bringing him in, Batman already has Joker in a chokehold when they come on again.
A doctor interviewing the Joker in one of the hidden tapes displays a bit. When Joker tries his Multiple-Choice Past nonsense and says his dad was a cop who fell victim to Retirony, the doctor interrupts him by saying, "No, I've seen that movie. Let's move on."
Getting Crap Past the Radar: At one point you have to save two workers dangling over electrified water while Harley Quinn watches and taunts you. While you're using the Cryptographic Sequencer to get rid of the electric currents, she remarks, "A girl can have hours of fun with a toy like that." Seems like Quinn is used to using toys like that, if you get what I'm saying.
Good Is Not Nice: Early on, Batman saves a thug dangling over a pit of deadly Joker Gas. He then punches the thug unconscious right on the spot. POW.
Good Scars, Evil Scars: One of the Arkham guards has an extremely noticeable facial scar. He turns out to be less than trustworthy. Plus, Zsasz.
Good Smoking, Evil Smoking: When Gordan is kidnapped Batman notes he's smarter than he looks by leaving a trail of tobacco to where he's taken.
Goomba Stomp: Although rare (i.e. there's no automatic function allowing you to do a takedown this way), landing directly on top of a thug will knock down and stun them. One of the challenge rooms actually requires you to do this.
One of Joker's Stealth Takedowns has him punting a guard in the nuts from behind.
Batman gets in the act too. Some of his counter attacks target the groin. The ground takedown can also glitch how Bats and a henchman are positioned, so while the attack is supposed to be in the face, it can hit the back of the head, the butt, or well, anywhere.
Another counter/finisher involves Bats catching a mook's high-kicking leg, lifting even higher, then driving his knee right inna nerts. You will wince with sympathy, even you ladies.
If the mook has a stun baton and you use the combo takedown, Batman throws the guy to the ground, grabs the baton, then drives it right into his sack. Ouch!
And while this might be due more to the angle of the camera, when you break through Scarecrow's final illusion, the ray from the Bat-Signal fires right into his crotch. No wonder he's screaming.
The Guards Must Be Crazy: The Gun wielding mooks, in more ways than one. In the stealth parts of the game, they can be incredibly idiotic. It seems likely that Arkham's shock therapy programs have an unavoidable side effect of making the patients partially deaf and blind, as Batman can break open grates and choke hold mooks at arm's reach of the other guards without being detected.
The Arkham Guard Staff themselves are incredibly lousy. Not only did they utterly fail to hold off against any of Joker's unarmed goons, even after managing to reform after his initial breakout, but the security system of the entire island was completely compromised by Joker with the help of just two insiders, both of whom appeared to be relatively incompetent. What makes it even more frustrating is that a lot of the higher ups knew Joker was up to something.
How about the most basic mistake of cuffing the Joker with his hands in front of him? Cops don't do that to perps arrested for a traffic violation, much less insane mass-murderers. The Joker ends up demonstrating why cuffing him with his hands in front is a terrible idea when preparing to escape.
Of course more than once the Joker addresses this.
He's in the middle of the room. The middle.In plain view. Do you guys need glasses!?!
Guide Dang It: Riddler really put out some fiendish puzzles. Even if you find all his maps, working out where his "Spot the invisible-ink Riddler Question Mark" solutions are can be really hard if you don't have spectacular observational skills.
He Who Fights Monsters: Quincy Sharp. After he had spent years amongst the Asylum and their inmates, his mind had slowly turned murderous and insane, developing another secret personality: "The Spirit of Arkham". Before the events of the game, he had tried to kill Joker in his cell (failed badly), and had thought of lobotomizing Harley and burning Ivy alive.
Joker keeps trying to invoke this trope on Batman, and gets increasingly angry when Batman refuses to surrender to madness/murderous urges/ actual Titan monster serum.
Heal Thyself: A rather unique variant: Batman's health refills based on how much XP he's generated, either by fighting or by finding the Riddler's collectibles. So the better you do, the more health you get back. If you're playing really well, you may not even need that health boost at all.
He's shot with Titan and Batman still doesn't go Ax Crazy, and holds it off long enough to inject himself with the antidote!
Batman's fighting off the effects of Scarecrow's injected toxin, a dosage apparently potent enough to drive ten men insane!
100% Completion: The more Riddler trophies and riddles you get, the more Gallery material or bonus challenges open up. Get them all, and you catch the Riddler! Take that, you Insufferable Genius! Plus, the extra XP never hurts.
Harley: You'll never find him! He's in a secret lab in the gardens and... aw, crap!
Batman: Yeah, I know.
I Meant to Do That: When you find the first few Riddler trophies and / or solve the first few riddles, the Riddler will respond along the lines of this, usually with a snide jab at how he expected you to find it much sooner. Considering that it doesn't take him very long to get rather annoyed when you find more of them, this probably isn't true.
Ineffectual Sympathetic Villain: Okay, maybe she isn't entirely useless, but Harley was defeated pretty easily by Batman. Admit it: you felt a bit sorry for her when she was crying in her cell. Till you turn on Detective Mode and see she's perfectly calm while crying. And stealing glances every few seconds to see if you're still watching.
Interface Screw / Interface Spoiler: The game is one of those that tells you the name of an area before you enter it, so just before Scarecrow's second fear-gas trip there's a split second where it tells you that your location is Wayne Manor.
A direct example of Interface Spoiler is the Visitor's Center. It's the only place on the island where you are locked into first person view and can't use any gadgets, suggesting that it will be significant later. Indeed it is.
The first time you are infected with the fear toxin it's not immediately obvious apart from the slight coughing and the Red Eyes, Take Warning, but if you use detective vision and pan over Gordon's 'corpse' it identifies him as 'unknown'.
Invisible Wall: The security force fields. There are also Invisible Walls which prevent you from killing mooks, e.g. by throwing them off a high ledge onto solid ground, or into electrified water.
Ironic Echo:In the game's prologue, where you escort Joker to the holding cells, Quincy Sharp appears on a monitor bragging about his accomplishments, one of which is the rehabilitation of Harvey Dent. At the ending Batman finally leaves Arkham when he learns Two-Face just robbed a bank.
Batman's scarecrow induced hallucination features a few of these, as it is essentially the game's introduction with the roles reversed.
As the Riddler starts growing more and more incredulous at the number of his challenges you've completed, he at one point makes the following comment:
Riddler: What? You're nearly done? Are you cheating? Looking them up on the internet? Tell me!
You could even say the quote actually makes more sense in a fourth wall context than in-universe, since the idea that, say, the locations of Riddler Trophies somehow got posted online and Batman looked them up on Google is pretty absurd.
When you visit the visitor's centre for the first time, the Joker asks Batman what his identity is and why he fights. However, it seems like the question was more directed toward the player, rather than Batman himself. The fact that this sequence forces the camera into first person lends credence to that idea.
Joker: Come in! Sit down! Take off your mask! So Bats, I was thinking: you could really use a friend in here. Someone to talk to, share secrets with. Shall we start with the big one? Who is that behind the mask? Why do you feel the need to go out into the world and fight people like me? Do you really think you can win? We'll see...
A very subtle example at the end of Killer Croc's level. Right before you detonate the gel to take Croc out Batman shouts "Now!". Who exactly is he talking to? Himself? Or... the player?
Magic Pants: The venom/Titan mutants and Joker Titan are (thankfully) wearing these.
Male Gaze: Used with Harley and Poison Ivy via the camera (and by proxy, the player) (Batman himself ignores their sexuality). The latter could be considered part of her powers but the former is clearly just fansevice as she herself points out.
Manipulative Bitch: Harley attempts this on Batman. Detective mode reveals that she's faking it. Should save that for Joker.
Mind Screw: The Scarecrow pulls this in-game, on both Batman and the player. See Fission Mailed above. At least Bats coughing gives it away, or Eternal Darkness would get a serious run for its money on the oh-crap-did-my-console-break side of things. There's a particularly famous example, which imitates a PC/console crash, that has spooked a significant chunk of the playerbase before they realise what's going on.
Monster Clown: The Joker, as usual. And his face-painted mooks, though not nearly at the same order of magnitude. Once the Joker gets the Titan formula working, Batman starts encountering literal monster clowns.
Mood Swinger: The Riddler. While he generally undergoes a gradual Villainous Breakdown in his appearances in the main plot, his tapes reveal that one minute, he's as charming as an Insufferable Genius can be, while the the next minute, he's screaming and ranting. In the final tape, Dr. Young even admits that she can't handle his violent mood-swings and is just palming him off to another doctor's care.
Mook Chivalry: Sort of played with. When you drop in on a group of unarmed mooks, they will surround you and just stand there until one attacks on his own. Eventually, though, they work up the nerve to gang up on you; they don't attack simultaneously but it's downright common for one mook to try and hit you in the back of the head with a baseball bat while you're engaged with another. Fortunately, the combat system is incredibly smooth, and allows for seamless transitions from fighting one enemy to another.
When you head into the Visitor Corridor for the last time there are 20 Mooks that just stand there clapping for you. You can walk right past them. But if you beat all of them up you get the Party Pooper achievement.
Played straight during special attacks. The mooks will politely wait for Batman to finish up before continuing the fight.
Mook Horror Show: Those poor bastards, having to go against a shadow who can easily thin out their numbers without them noticing.
Ms. Fanservice: Harley Quinn. And yes, Poison Ivy's being a hot green-skinned redhead wearing only a prison shirt and leaf underwear definitely counts.
Multiple Endings: Sort of. The Stinger has either Scarecrow, Bane, or Killer Croc reaching out of the water and grasping a crate of Titan.
Multi Mook Melee: Very much so, particularly with the various brawling challenge modes.
Murder.com: The Joker briefly thinks of doing this (or at least floats the idea around).
My Name Is Not Durwood: The Spirit of Arkham references a "horrible name" people call him. Given there's only one thing Joker ever calls the warden, we can gather he really doesn't like being called "Sharpie."
Mysterious Backer: In Road to Arkham, a prequel tie-in comic to Arkham Asylum, Batman notes that all three of his captures (including The Joker) were given via anonymous tips, and he has a gut feeling that they are from the same person, asking Oracle to go over the tips. Who the anonymous tipster was is unknown, although evidence from this game as well as the sequel implies that it is either Quincy Sharp, Dr. Strange, or Ra's Al Ghul.
Naughty Nurse Outfit: Harley trades in her usual jester catsuit and motley hat for a fetish nurse outfit when she becomes the de-facto administrator.
Never Trust a Trailer: The game's ad campaign was based entirely around stealth, to the point where it gave the impression that Batman had snuck onto the island and had to spend the entire game in the shadows, lest the Joker blow up those bombs of his.
Also, several of the "character" trailers significantly over-represented the characters they referred to. This was especially the case for the Harley Quinn trailer, which foreshadowed a fight between Harley and Batman; in the actual game, Batman defeats Harley in a single blow at the moment immediately after the trailer cut out.
New Powers as the Plot Demands /Strong as They Need to Be: When Batman needs a new piece of equipment to get around, he gets it from the Arkham Batcave, the Batmobile, and the Batwing. When the suicide collars are added to the mix, the Sonic Batarang can be enabled, meaning he had them, but didn't use them. Likewise, Batman always had the Cryptographic Sequencer on him, but he needed the warden's codes to make it work.
No Ontological Inertia: Averted: Once you defeat Poison Ivy, the giant vines she sent out will wither and die, thus no longer blocking you from the last Riddler trophies, but they'll still be around. In a more mundane example, if you intend to keep playing after the main storyline to track down riddler trophies and such, you best not forget about the explosives planted on gargoyles. They are still there and are one of the few things that can kill you.
All the Titan-enhanced people, after growing to something like five times normal size and having their vertebrae force their way through the skin of their backs, all change back to normal after the game. However, the sequel makes it clear that doing this causes some serious long-term health problems.
Not So Different: In the patient tapes, the Riddler's convinced that Batman's a criminal like he is, he just steals from other criminals and bribes the cops. Joker's interviews reveal he has much the same attitude towards Batman; that he's as crazy as anyone else in Arkham, but he's got everyone fooled into believing he's a hero.
Offhand Backhand: Thanks to the combat system, it's pretty simple to take down a mook who's trying to hit you from behind and look stylish while doing it. Batman pulls off the classic version seen about once an episode in BTaS on a mook in a custcene towards the end. At the end, it happens not once, not twice, but three times. You'd think those inmates would learn eventually.
Oh Crap: You cause this in the Mooks, but you also cause it to Scarecrow when you beat the last of his challenges.
Scarecrow: You just ingested enough toxin to drive 10 men insane! What are you?
When you confront Scarecrow again in the sewer, he'll threaten to poison the Gotham River, but when Bats approaches anyway, Scarecrow backs away.
Also, in the ending, if you look close, Titan Joker will see the explosive gel on Batman's glove right as the punch connects.
Damn you, Rocksteady, and that fake Scarecrow glitch!
Optional Stealth: In most of the areas if you feel lucky you can bring down all the nearby mooks with violent means. However, stealth is safer, especially when gun-toting enemies are around.
Painting the Medium: Certain attacks have medium-painting effects; for instance, when Batman takes damage from electricity, the screen develops interference patterns as if there were actually an electrical discharge nearby. Also, at one point in the game, there's a dramatic graphical glitch and then the game restarts from the opening cinematic — with certain... disturbing... differences. It's another fear gas attack from the Scarecrow.
Destroying one of Poison Ivy's killer plants causes goop to fly everywhere, with some of it getting on the "camera".
Similarly, walking through the waterfall in the Batcave makes water cover the "camera."
Patrolling Mook: Later in the game, Mooks will have devices on them that alert each other if they are knocked out, causing the rest to be more cautious and more scared.
Also, Scarecrow, who has what can only be described as a syringe glove.
Plot Irrelevant Villain: To an extent, Bane: he shows up once to fight Batman and gets taken down for good in the next cutscene. He has a greater indirect role in the plot, however, in that it's his blood that Titan's being made from and Joker starts making to Hulk-out all of Gotham.
Police Are Useless: The GCPD's main role in this game is to quarantine Arkham Island, and to arrest all surviving villains at the end of the game. They aren't even visible until the end cutscene. Island-side, Arkham's security demonstrates a complete inability to stand up to armed criminals and mutants. Looking back, it's actually kind of funny that The Joker escapes from them as soon as he's more than thirty feet away from Batman.
Railing Kill: Well, Railing Bonk, anyway. In the event that the railing is really high up off the ground, Batman thoughtfully attaches a bungee cord to one of their legs as he tosses them over the side so they won't die.
Arguably even more so with the Blackgate inmates. The guards can't stop an army of murderous felons, but those same felons can't even stop what is ultimately, as Joker himself lampshades, just one man.
Reptiles Are Abhorrent: Well, actually Croc's just a human with a "skin condition", but he is definitely reptile-like, and very, very abhorrent. A really bad skin condition. It is possible that, like in the comics from 2003 onwards, he's meant to have been infected with a virulent mutagen that's made his condition even worse, but the game is silent, as Batman is more concerned how he wants to use his femur as a toothpick.
Retirony: In a recording of one of the Joker's patient interviews, his doctor asks him about his childhood, and he claims that his father was a cop, who was a week away from retirement when — but we don't get to find out what happened then, because at this point the doctor decides that he's just making it up (the doctor's seen that movie already), and changes the subject.
Rewarding Vandalism: If you want to solve all of the Riddler's riddles, you're going to be destroying a lot of walls and security terminals. In addition, a lot of takedown moves involve breaking through walls, windows, ceilings, and floors. Batman isn't known for arbitrary property damage, and there are more conventional boxes and such around, but they are either indestructible or cannot be interacted with.
Individual rooms full of crazy can be found for bad guys such as Two-Face, the Calendar Man, Maxie Zeus and the Riddler, amongst others.
Role Reprisal: As stated, Kevin Conroy reprised his role of Batman, Mark Hamill reprised his role of the Joker and even Arleen Sorkin reprised her role of Harley Quinn for this game(Though in the sequel, she was replaced by Tara Strong)
RPG Elements: You gain experience when you beat enemies or explore around, and when you level up, you can choose between different upgrades such as getting a new combo, getting more health, upgrading your gadgets, etc. It's firmly in the territory of this trope as there's no need for specialization: by the end of the game (assuming you've been following the Riddler challenges) you'll have enough experience for every upgrade in the game and then some.
Sanity Slippage: The Spirit Of Arkham messages, for both Amadeus and Sharp.
Sanity Has Advantages: Inverted. It's heavily implied that the reason why the Joker retained his mind shortly after injecting himself with the Titan serum is precisely because he lacked sanity to begin with.
Scenic Tour Level: Escorting the Joker through Arkham in the intro. Interestingly enough, you can take time to talk to the people you meet during this part and learn some new things you wouldn't otherwise. Killer Croc used to be a drug dealer before he mutated, and he's moved through Arkham, he's pumped full of tranquilizers.
Schrödinger's Gun: In the morgue, during the first Scarecrow hallucination, you are confronted with three body bags. Whatever order you open them in, the contents are always Bruce's father, then his mother, and finally Scarecrow. Also, no matter what order you collect the audio tapes in, they are always the next one in the set. Same goes for the Spirit of Arkham messages.
Sequel Hook: During the ending, there's a news report of Two-Face's robbing a bank, to which Batman presumably flies. Also, The Stinger has Bane, Croc, or Scarecrow's hand (chosen randomly) getting hold of the Titan formula.
Also, take a close look at Ra's al-Ghul's body bag in Dr. Young's office before and after beating the game.
And Tommy Elliot, AKA Hush, is a doctor at Arkham.
After finding all the Spirit of Arkham messages, go back to the room where you left Warden Sharp for his own safety. The room is empty, and has the word "Batman" scribbled all over the floor.
Go to the warden's office, as seen here. The middle section of the wall can be blown down with multiple gel charges, revealing a secret room with blue prints and photos providing a sneak peek at the sequel.
Sequence Breaking: After fighting some thugs in the Arkham Mansion library, you go down the stairs to see the Joker gloat as there are poor people hostage. You can, however, go straight to their rescue after beating up the thugs, and the Joker will call you out on it.
Don't even have to beat up the thugs: you can grapple up as soon as you enter the room in which case the Joker will berate his mooks for not even being a distraction and summarily dismiss them. Which incidentally sidesteps the possibility of Batman killing them by dropping a ridiculously large chandelier on their heads.
There's actually several places where scenes play out differently if you try to Sequence Break, usually if you try to enter a building through the front door. Harley (or several other thugs) will be safe behind a forcefield and taunt Batman. It's particularly delicious to get the drop on the ones who were taunting you moments earlier.
Especially since they're relating the incident (and Batman just up and leaving) to their disbelieving companions.
Shell Shock Silence: Batman experiences one of these near the end of the game, after the Joker triggers his booby-trap
Shipped in Shackles: This is how The Joker was wheeled into Arkham in the first scene. Batman gets the same treatment later in a Scarecrow-induced hallucination.
Shock Collar: The only way to take down Killer Croc is to use the one installed on him.
Shoot the Shaggy Dog: Batman rescues Dr. Young from Zsasz, only for her to die a mere minute later in a trap the Joker set for her.
In fact, fight scenes in rooms where Batman primarily uses stealth had the inmates reacting eerily like mooks from various Metal Gear Solid games; i.e., take one out, another comes across his unconscious body and he immediately calls over all the others in the room. They slowly move out, sometimes covering each other's backs and are far more careful than before. One can almost see the yellow Caution! timer at the top of the screen.
Speaking of the stealth parts, there's a reason why the devs nicknamed it "Predator gameplay".
The "Tick, Tock, feed the Croc" is a reference to the crocodile in the Peter Pan stories.
It's also a reference to the mini-series Arkham Asylum: Living Hell, where Killer Croc says it to Arkham security guard Aaron Cash (whose hand he had bitten off some time ago, giving Cash a phobia of him).
Cash's hook-hand is a clear reference to Captain Hook, who ever so coincidentally got his hand bitten off by a crocodile.
Shut Up, Hannibal!: What's that, Joker? You think you're going to win? "I'll never let you win. Never." EXPLOSIVE PUNCH.
Also, whenever any of the inmates tries to psych out Officer Cash, his typical response is along the lines of "You wait until I'm not in this death trap you put me in, and I'll shove those words up your ass."
One from Batman:
Bane: I will break you Batman! First you, then the Bruja!
Batman: No Bane, this time I break you!(the Batmobile slams into Bane, sending him into the water.)
Slave Mooks: The Titan Monsters work as this trope, as are Poison Ivy's slaves.
Also, the Joker seems to be threatening the families of at least some of the inmates.
Sleazy Politician: Despite a massive prison takeover and Joker unleashing havoc on Gotham, Warden Sharp's only concern is his upcoming political campaign.
Small Name, Big Ego: The Riddler comes off like this when he hacks Batman's comm system. Every so often, when you discover a riddle, you'll get a message from him along the lines of saying that obviously he intended for you to find that one and he's astonished that you didn't find it before now. Then you find more of them. Gloating becomes genuine astonishment. Then you find even more. Astonishment becomes white hot fury.
Square/Cube Law: Batman is six-two and weights 210 pounds. Killer Croc is 11 feet tall and weighs 580 pounds (changed in the sequel to 9 feet tall and 320 pounds). Either Croc is full of mostly air or he should weigh three or four times that. Interestingly, though, the game itself seems to treat his weight as more realistic; an elevator that visibly strains to lift him has no trouble with four people and a reinforced gurney afterwards. It's possible the developers knew the weight figure was severely off but couldn't change Croc's bio, so just ignored it.
Start of Darkness: If you find her patient interview tapes, you get to listen to Harley Quinn's.
Stating the Simple Solution: Harley doesn't mind if the goons shoot Bats, even asking them to just grab a gun and shoot him in the Penitentiary.
The guards really just want to put a bullet in the inmates head, and given the inmates it's a little hard to blame them.
Stealth-Based Game: But rare for the genre, it often isn't obligatory. The developers called it "Predator-based" gameplay, as the player is not so much hiding as patiently waiting for a chance to strike.
Stealth Pun: Ivy is wearing planties. That or it's her "bush". And guess where she's being kept? The Green Mile.
The Stoic: None of the crap Joker, or nearly any villain, does freaks Batman out. Only Scarecrow is able to get some kind of reaction, but that's more the effects of his gas. It's pretty obvious when you find the Titan-flooded old sewage chamber and Batman says there's a new problem. It sparks this conversation:
Oracle:(exasperated) What now? Riddler? Two-Face? Some kind of giant Joker robot? Batman: Unfortunately, nothing that simple.
Stripperiffic: Ivy's only wearing a prison shirt held closed by one or two buttons and leaf underwear. Harley to a lesser extent with her nurse outfit.
Super Drowning Skills: Played with; though Batman doesn't drown if he jumps into water, he doesn't progress either. The player gets a cutscene of him pulling himself out of the water and is returned to the last safe spot they were at.
Superman Stays Out of Gotham: But only because Joker threatens to detonate random bombs around the city if he sees anyone in a cape besides Batman.
Killer Croc doesn't have to come up out of the water and engage you on the walkways.
Poison Ivy doesn't have to open up her protective shell while she's bombarding you with spores. Although she's a bit of an exception in that she takes some damage from being attacked otherwise, just not enough for any but the most skilled players to beat her without waiting for her to... er... expose herself.
Titan Joker doesn't have to turn his back on you.
Technical Pacifist: After dispatching enemies, if you turn on the visor and scan them, they're just unconscious.
If you ever manage to yank a henchman into a bottomless pit, you'll typically hear a splash so that you don't break Batman's no-kill policy.
That's Gotta Hurt: Batman's only rule is not to kill his enemies, but that rule says nothing about their physical state after he's done with them. Nearly every move in your arsenal evokes this trope. Drive a guy's face into your knee? Check. Pull an enemy over to you with a claw on a rope and roundhouse him across the face? Check. Land on a prone guy's body and megatonpunch him in the groin? Double check. Then there's the instant takedown moves, which usually involve actions like ramming a stun baton into a guy's solar plexus or breaking his limbs in a variety of ways. Ouch.
Throw Batarangs at the TV: Batman can throw batarangs at most TV monitors which the games' villains appear on, cracking the screens.
Tragic Monster: The Arkham Lunatics are this, especially when the sequel strongly implies that Dr. Strange is the reason why they are currently rabid.
The Unfought: Of all the villains gathered for the game, Bane, Poison Ivy and the Joker are the only ones you get a proper boss fight with. Harley and Scarecrow are taken out in cutscenes, Zsasz is defeated with a single stealth attack and Croc just gets beaned with a few batarangs and then gets taken out in a cutscene.
Unhand Them, Villain!: In the Botanical Gardens. (To be fair, the guard isn't dangling over deadly peril when Batman says "Let him go!" — the Joker deliberately shifts before letting go.)
Unspoken Plan Guarantee: Batman pulls it a couple of times like calling the Batmobile to run over Bane, just after the guy has (supposedly) been defeated - how Genre Savvy of you, Bats! Most importantly, he pulls one on the player. Better figure it out before Killer Croc reaches you, or you're toast.
Victoria's Secret Compartment: Well, not so secret considering how much cleavage she's displaying, but Batman steals the Joker's party list out of the front of Harley's top after defeating her.
Video Game Caring Potential: A minor example, but worth mentioning: When you first enter the Sanatorium, you see Dr. Cassidy "escorted" by a thug to where the other hostages are being held, where she kneels sobbing and scared. If you go nearby her prior to eliminating all of the thugs, she'll stop sobbing and whisper "Batman?" who will tell her to stay put since it's not safe yet. For the rest of the time you're busy eliminating the thugs, she isn't crying anymore.
Video Game Cruelty Potential: Granted this is a lighter case, but once you've leveled up a bit, you can get downright vicious on the Mooks; you can combo throw them into other Mooks, over a railing into pits, or into the electric doors. Using the weapons, you can knock them off ledges with batarangs, yank them over ledges and catwalks with the Batclaw, make landmines with explosive gel, etc. And this barely covers what you can do in the game.
Then there's the trick with inmates dangling from ropes. You can earn an achievement/trophy for launching a batarang and severing the rope holding them up. One level actually requires you to do this; you need to clear a room of Joker Toxin by throwing batarangs into the starters of the vent fans to suck the gas out. In order to reach the last one, you need to sever the rope of a helpless dangling inmate to allow him to break the roof of the room below, whereupon you hear him start to laugh maniacally as the Toxin takes hold. Granted, Batman emphatically states afterward that he can't let the guy die like that, but the temptation is rather... delicious, shall we say?
You know the first inmate you find clinging to the grating over the gas-filled decontamination chamber? You don't have to rescue him.
If psychological cruelty is more your thing, you can have hours of fun reducing a crew of heavily armed henchmen from tough, sadistic thugs who confidently boast about the atrocities they've committed against the guards and what they'll do to Batman when they get ahold of them into terrified little cowards practically wetting their pants at every tiny noise just with a vantage point, a few batarangs and the willingness to take each man apart one at a time...
Mook: *screams; repeatedly shoots at machinery* ... Damn boiler scared the crap out of me.
The rope trick can be done with the ropes used in Vertical Takedowns. Meaning you can snatch a guy from out of nowhere to scare the crap out of him. Drop him 10 feet to scare more crap out of him. And then when he thinks he's (relatively) okay, drop him again on his head.
It's even possible, when cutting him down, to make him land on another guy, taking that guy out.
One particularly fun move becomes available after upgrading the explosive gel so that it will act as a proximity mine. Spray it on the top of a ladder and just wait for a henchman to climb up the ladder, at which point, the unfortunate slob will be sent cartwheeling through the air like the animated rag doll that he is, which is far more effective than just spraying the gel on some random point on the floor (which just stuns the mook). Another good one is that one section of breakable floor found in the sanatorium/Silent Knight challenge level). Go to the room underneath it and spray the gel on it from below as close to the center as you can get. Then go up topside and wait for the unfortunate mook to walk right over it. If you time the detonation right, you can send the poor schmuck flying as high as the gargoyle you're sitting on.
Villain Team Up: There is tons of evidence that the Riddler is working with Joker. As usual, he's working with Harley, and judging from his comments in the Medical Facility he might have made an alliance with Bane and Scarecrow, too.
Wham Line: From Warden Quincy Sharp, when the player finds one of the Spirit of Arkham messages, and realizes it's not written by Amadaeus Arkham, and is actually contemporary.
"Yet again I found myself watching him. No one can provide a cure. He laughs in the face of those who try. Amadeus would not have let him live and neither should I. One last sip of cognac and I was ready."
What Happened to the Mouse?: Zsasz is MIA after you save Dr. Young from him. There's the Scarecrow vision, but that's an illusion. Same thing applies to some of the named staff in Arkham after you save them.
Woobie, Destroyer of Worlds: The Lunatics that Joker released, although certainly threatening and dangerous, almost have to be pitied for their fragile mental state and rabid behavior that was the result of the conditions in Arkham Asylum.
You Have Failed Me: One of Joker's radio chatter lines uses this word-for-word if you've taken out all but one or two Mooks.
Likewise to Harley after she fails to stop you. He doesn't kill her, but just tells her she's "off the party list".
You Have Outlived Your Usefulness: Guard Boles is killed shortly after helping Harley kidnap Gordon. Upon finding his corpse, Batman mentions that he must've outlived his usefulness.
You Have Researched Breathing: Batman carries a seemingly limitless supply of Batarangs in his Hyperspace Utility Belt. One of the upgrades is the ability to throw two Batarangs at once. Then three. And the ability to throw three Batarangs is separate from the ability to throw one at a time, and requires recharging (but one can still throw three individual Batarangs in rapid succession).