Alternate weapon view
Equip the Batarang, Batclaw, or Multibatarang, then press LT to aim and RB to fire the weapon to get a behind-the-projectile view.

Solving The Riddler's "?"s
If you are perplexed by The Riddler's more difficult riddles such as "What's right in front of you but still hidden from view?", you will usually be able to use Detective mode to find a piece of a question mark without a dot (or the dot without the question mark). An easy way to see an example of this is to go to the second balcony outside of the penitentiary. Look toward the medical facility, and enable Detective mode. You will see a "?" with no dot under it on the floor. Grapple to the balcony above, and on the center pole of the railing is the "?"'s dot. Align them onscreen, and use Environmental Analysis. This will solve the "Do you see what I see? No? Then maybe I am in a stronger position." riddle. There are only a few of these riddles, but you must find both parts of the "?" and align them to solve the riddle.

"Solve The Spirit Of Arkham's Mystery" chronicle
If you are skilled enough to find all of The Riddler's secret maps, or if you find all the "Chronicle Of Arkham" hidden pieces throughout the game without them, there will be one more blank chronicle remaining to decipher. To unlock it, go all the way back to where you found Clayface behind the wall in the penitentiary. Go up the center stairs where you left Warden Sharp a long time ago. There will be some scribbling on the floor. Use your Environmental Analysis on it to unlock the final chronicle.

Easy combos
When fighting a Titan henchman along with a group of normal henchmen, stun the Titan, then jump on his back, and use him to hit the normal henchman to increase your combo total.

Defeating Bane
Bane's primary attack is similar to the trample done by the deformed Joker henchman. When Bane begins to run towards you, throw a Batarang at him, then dive out of the way. Bane will run into the wall and will be momentarily stunned. While he is stunned, start hitting him. Batman will then jump on top of Bane and rip off one of the hoses pumping him with venom. If your Batarang misses Bane, he will still run into the wall and appear to be stunned; however, he will just cover his face and try hitting you. When he turns around, run away from him. After you rip off the first hose, prisoners will jump from the railings and try to help Bane, and Bane will throw chunks of wall at you. You can focus on them or just try dodging them while focusing on Bane. Pull three hoses from Bane's back to defeat him.

Defeating Poison Ivy's plants
To destroy Poison Ivy's large plants on the ground, get near them to pull out the heart by dropping from above. Find a high point such as a tower or building, then drop down directly beside it. The plant will not have enough time to produce the irritating orbs that can hurt you before you tear its heart out.

Frank Boles information
There is an advertisement in the Medical Facility for the hospital's website (www.ArkhamCare.com). You can visit this URL in a web browser and use the employee login section. Enter "125845712" as the guard login number. You will login as Frank Boles and can read information about him.

Ras Al Ghul's resurrection You can find Ras' corpse in Dr. Young's office. If you re-visit the office later in the game, Ras Al Ghul's body bag has been unzipped and his body is missing, showing that he once again resurrected and escaped.

Arkhamcare website In Intensive Treatment, there is a long hallway (where Scarecrow first attacks you) where you will hear a recording that talks about how to treat patients. It tells you that you can find pricing information at http://www.arkhamcare.com/prices/, which is a real website.

Batman RIP reference During the final confrontation with Scarecrow, it shows Batman's gravestone, which is the same design as the current comic book series Batman RIP.

Knightfall reference If you lose to Bane, it shows a cutscene of him snapping Batman's back over his knee. This is reference to Knightfall: Book 1, where Bane breaks Batman's spine.

Scarecrow actor references
Listen to the first Scarecrow interview. You will hear him mention a Dr. Murphy, and a Dr. Combs will be mentioned by a security guard. Cillian Murphy played Scarecrow in the newer movies and Jeffrey Combs voiced Scarecrow on the later episodes of Batman: The Animated Series.

Easy "Mano-A-Mano" achievement
This trick requires the Proximity Detonation Explosive Gel upgrade. In Challenge mode, select "Rumble In The Jungle". Make it through the first three rounds, conserving as much health as possible. In Round 4, do not engage the Titan until everyone else in the room (Arkham inmates) have been defeated. Do not use a Batarang -- if you hit the Titan with it at all you will not get the achievement. Immediately switch to your Explosive Gel, and wait for the Titan to charge at you. Be careful because there is always a chance he will throw a dead body at you first. Dodge the charge, then set one of your own (spray the floor with Explosive Gel; it is best to do it immediately after he rushes at you, and make sure you let Batman completely spray the gel). If possible, stand over the area you sprayed. When the Titan charges again, dodge, and the Explosive Gel should detonate. The explosion does not take much health off the Titan, but it does not matter. After he takes a big blind haymaker punch, attack him. You can build up a twelve to fifteen hit combo on him before Batman delivers the knockout blow earning you the "Mano-A-Mano" achievement.

Easy "Night Glider" achievement
Reach the highest point of Arkham Mansion in Arkham East (the clock tower), then glide down.

Achievements
Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Big Bang (50 points): Complete story mode on Easy difficulty.
Bigger Bang (50 points): Complete story mode on Normal difficulty.
Biggest Bang (50 points): Complete story mode on Hard difficulty.
Party Pooper (10 points): Time to break up this party.
Freeflow Combo 20 (10 points): Complete a combo of 20 moves (any play mode).
Freeflow Combo 40 (10 points): Complete a combo of 40 moves (any play mode).
Night Glider (5 points): Glide continuously for over 100m.
Rope-A-Dope-A-Dope (10 points): String up one henchman and drop him to surprise a second (any play mode).
Mano-A-Mano (10 points): Take on a beast in hand to hand combat.
Catch! (5 points): Catch a Batarang (any play mode).
Freeflow Combo 5 (5 points): Complete a combo of 5 moves (any play mode).
Freeflow Combo 10 (5 points): Complete a combo of 10 moves (any play mode).
Freeflow Perfection (10 points): Perform a perfect combo including all of Batman's combat moves (any play mode).
Freakshow Rodeo (10 points): Ride a beast and unleash its power.
Freeflow Bronze (10 points): Achieve 8 medals on combat challenges.
Freeflow Silver (25 points): Achieve 16 medals on combat challenges.
Freeflow Gold (50 points): Achieve 24 medals on combat challenges.
Predator Bronze (10 points): Achieve 8 medals on predator challenges.
Predator Silver (25 points): Achieve 16 medals on predator challenges.
Predator Gold (50 points): Achieve 24 medals on predator challenges.
Invisible Predator (10 points): Complete one predator challenge by using only Silent Takedowns and without being detected.
Flawless Freeflow Fighter (10 points): Complete one combat challenge without taking damage.
Crack The E Nigma (20 points): Solve every riddle on the island.
Arkham Analyst (20 points): Solve 5% of Riddler challenges.
Cryptic Investigator (20 points): Solve 10% of Riddler challenges.
Lateral Thinker (20 points): Solve 25% of Riddler challenges.
Mystery Solver (20 points): Solve 40% of Riddler challenges.
Conundrum Cracker (20 points): Solve 55% of Riddler challenges.
Mental Athlete (20 points): Solve 70% of Riddler challenges.
Riddle Resolver (20 points): Solve 85% of Riddler challenges.
World's Greatest Detective (20 points): Solve Arkham's biggest mystery.
Perfect Knight (75 points): 100% Complete.

Additionally, there are fifteen secret achievements:

Shocking Rescue (10 points): Take down Zsasz in the Patient Pacification Chamber.
Leave No Man Behind (10 points): Rescue the guards and henchman from the Joker toxin in Decontamination.
Malpractice Needs More Practice (10 points): Survive the onslaught from the deformed Joker henchman.
Born Free (10 points): Escape from Intensive Treatment to the island surface.
Just What The Doctors Ordered (10 points): Save all the doctors in Medical.
Daydreamer (10 points): Survive the nightmare of the Scarecrow's fear gas.
Baneful Payback (25 points): Defeat Bane.
Breaking And Entering (10 points): Gain access to Arkham Mansion after it is locked down by the Joker.
Recurring Nightmare (10 points): Face your biggest fears and keep your sanity.
Zsasz Cut Down To Size (10 points): Save Dr. Young from being killed by Victor Zsasz.
Solitary Confinement (25 points): Capture and lock up Harley Quinn.
Double Trouble (25 points): Defeat two Titan Henchmen at once.
Resist The Fear (50 points): Conquer the effects of the Scarecrow's fear gas.
Crocodile Tears (50 points): Venture into Killer Croc's lair and come out alive.
Poisoned Ivy (50 points): Defeat the giant Titan Ivy plant.

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