Arkham City is an open world action-adventure game that incorporates elements ofstealth and beat 'em up game tactics. The gadgets obtained in the first game are present at the start of Arkham City, while others become available during play. Most of these gadgets have improved or new capabilities; for example, the Cryptographic Sequencer can also track signals, while the line launcher can now be deployed as a tightrope that allows Batman to flip and launch another zipline to switch directions. The remote control Batarang now has a built in brake and boost. The grappling gun can now be used while gliding to lift Batman higher into the air. New gadgets include smoke pellets to confuse and distract armed enemies, the Remote Electrical Charge, a taser gun that can be used to power generators and shock enemies, ice grenades that freeze enemies and make walkways across water, and a signal disruptor used to jam firearms and detonate enemy explosives.

The game incorporates more puzzle elements than its predecessor; the use of Batman's "Detective Mode", which highlights elements such as enemy skeletons and clues on-screen, is used to perform forensic activities such as backtracing a sniper round. The player has access to a criminal database that tracks forensic puzzles and several investigations across the city, as well as a communications interception and tracing network.^[14] However, Rocksteady's art director David Hego described the new detective mode as an "augmented reality mode", and game director Sefton Hill has also stated that although enemies and evidence can be seen more clearly, the navigational part is toned down as they found that some players completed Arkham Asylum using detective mode throughout almost the entire game.^[15]

Optional challenges from the Riddler to collect hidden trophies placed around the city are also present, but require additional effort to locate, such as interrogation of the villain's henchmen and the use of nearly all of Batman's gadgets to disable traps and barriers placed around them. After a certain number of trophies are found, Batman must rescue a hostage that the Riddler has captured, which requires him to disable death traps set by the Riddler.^[14][16]

Batman defeats an enemy in a demonstration of Arkham City's "Freeflow" combat system.

The player controls Batman through Arkham City to complete mission objectives. In addition to the primary mission, the game introduces secondary missions featuring key characters and their stories. The player can opt to move silently, avoiding inmates and other enemies using a combination of gadgets to sneak up on enemies to incapacitate them. Batman's gliding ability allows players to dive downward and pull themselves back up, enabling the player to traverse the city by air. At other times, the player may be forced to fight inmates using an improved version of the Freeflow combat system from Arkham Asylum, allowing for multiple simultaneous counters, the ability to counter thrown objects, jump attacks, powerful multi-strike beat-downs, upgraded Batarang and Batclaw attacks, and the ability to use gadgets such as Explosive Gel. The formation of gangs and territory between rival villains, such as Two-Face, The Penguin and the Joker, causes in-fighting that complicates movement.^[14]

Catwoman is another playable character with her own heist-focused storyline at specific points in the game. Her combat is more acrobatics-oriented and features her claws, whip, and bolas.^[17][18] She has her own version of Detective Mode called "Thief Vision" to locate items to steal

Dax Ginn revealed at Gamescom that the game has about 40 hours of gameplay with the main campaign lasting 25 hours and 15 hours for side missions.^[19][20] The game contains 440 Riddler challenges, which make up one of the multiple side missions that players can undertake.^[21] Rather than rely on maps, the player can mark Riddler puzzles as they are found, if the player does not have the necessary equipment to complete them. A portion of the puzzles are specific to Catwoman and can only be completed by her.^[22]

The Xbox 360 and PlayStation 3 versions of Arkham City include a stereoscopic 3D mode for 3D HDTVs and for 2D HDTVs via Inficolor 3D glasses, while the PC version supports Nvidia 3D Vision which allows an even greater 3D depth. It uses TriOviz for Games Technology, which is integrated with Unreal Engine 3. All Arkham City gameplay and cinematics have S3D support.^[23]

Catwoman

Selina KyleCatwoman

Her agility and razor-sharp claws will buy Catwoman some time in Arkham City, but without a strong ally or power base it is unlikely that she will remain unscratched for long.

Catwoman's best chance is to team up with one or more of the other villains, who are able to offer her some protection in return for her special skills -- she is perhaps one of the greatest thieves in the world.