Batarang

The Batarang is a bat-shaped projectile weapon commonly used by Batman and his associates as a non-lethal ranged attack, and an alternative to firearms.

Both Robin and Nightwing had their own versions of the Batarang, respectively the Shuriken and the Wing-Ding.

Gameplay
The player had an unlimited supply of Batarangs which could be equipped by holding L1/LT/RMB (PS3/XBOX360/PC) and thrown by pressing R1/RT/LMB (PS3/XBOX360/PC). You could also initiate a "Quick Batarang" throw by just tapping L1/LT/Q (PS3/XBOX360/PC ) and it hit the closest or most important target without fail.

Batarangs stunned enemies that didn't see them coming. In combat, Batman could chain them into his combos following an upgrade.

Characters using Batarangs or similar weapons (Bolas, Shuriken, Wing-Ding) prioritize throwing with their right hand, and the projectile in question tends to curve to the right. Throwing Batarangs from the right position is very useful, for example, to easily knock henchmen off ledges and take them out. The same also goes with the Reverse Batarang.

Before Arkham Origins
Due to Batman's no-killing rule, standard ones can be used as throwing weapons to strike and potentially knock out an opponent from a distance or distractions to lure them into an area for Batman to take them out stealthily. They were also stored with relative ease in the utility belt because of dual quick release collapsible hinges. Based on the task at hand, Batman carried a variety of Batarangs from Sonic Batarangs, Sonic Shock Batarangs, and Remote Control Batarangs to travel a long distance.

Batman: Arkham Origins
The Remote Controlled, Sonic, Multi, and Reverse Batarangs all returned in Arkham Origins. A new Batarang was also introduced:
 * Explosive Batarang - Could only be used in Arkham Origins Multiplayer. Exploded and knocked out nearby enemies instantly and may draw thugs towards the explosion.

Batman: Arkham Origins Cold Cold Heart
Batman started out the DLC with the same Batarang options from the Origins story line. However, after Batman obtained the XE Suit, you could use the Thermal Gloves to use both Thermocharged Batarangs and Remote Controlled Thermocharged Batarangs. Both versions were capable of breaking ice formations around the city.

Batman: Arkham Origins Blackgate
The Shock Batarang appeared in Arkham Origins Blackgate. Its usage was to power and destroy electrical terminals and generators. This could also be used to stun enemies, though it would not incapacitate them like the Sonic Shock Batarang.

Batman: Arkham Asylum
While the standard, unfoldable Batarang was available from the start, upgrades to the weapon could be bought with XP through the WayneTech Upgrades Menu.

Batarang Upgrades included:
 * Combo Batarang - Powered up the Batarang during combos and allowed Batman to knock down thugs.
 * Batarang Power - Upgraded the standard power of the Batarang, and increased the time an assailant stayed down when they were hit.
 * Twin Batarangs - Could target two enemies at once.
 * Triple Batarangs - Could target three enemies at once.
 * Sonic Batarang - Attracted a nearby enemy.
 * Sonic Shock Batarang - Attracted and disables a nearby enemy. Could only be used once per encounter as it created interference in the area, which prevented future Sonic Batarangs from functioning there.
 * Remote Control Batarang - Could be steered through complex flights, and could take out several enemies at once.

Batman: Arkham City
Batarangs in Arkham City worked similarly to the previous game and served a similar function. However, Batman could no longer throw multiple Batarangs at once, although he could rapidly throw them.

The Sonic Batarang was unchanged, but the Remote-Controlled Batarang was given a large overhaul. While, in the previous game, the RC Batarang could hit multiple targets, in Arkham City it could only hit one before going out. However, Batman was given greater control over the Batarang's flight, and was able to slow it down, speed it up, and make U-turns. The RC Batarang was also used far more frequently to solve puzzles, such as hitting out-of-reach switches and disabling electrical boxes. The game also featured a new type, the Reverse Batarang. It allowed you to hit a thug from behind. Batman used the Reverse Batarang to defeat Ra's al Ghul later on at Wonder City in the game. After the boss fight, the new feature (Reverse Batarang) was permanently added to the Remote-Controlled Batarang.

Batman: Arkham Knight
The standard Batarangs were relatively the same as their previous counterparts, but could be thrown in while gliding, which gave Batman more versatility when he entered a fight. The Multi-Batarang has returned and are smaller than the normal Batarangs. The Remote Control Batarang was given a slower default speed, which made it easier to control, and was also used early on in the game to track radioactivity in Gotham. Like other thrown weapons, Batarangs knocked out a charging enemy immediately.

Freeflow
In Arkham Asylum, Freeflow allowed Batman to throw the Multi-Batarang (3 simultaneous Batarangs), but using it more than once in a row would break the combo. In Arkham City and Arkham Origins, only 1 Batarang could be thrown at a time, but 3 could be thrown consecutively, and a consecutive fourth one would break the combo; the Multi-Batarang could ever be used with the Freeflow Focus Power Gadget ability. In Arkham Knight, Batman could once again use the Multi-Batarang in Freeflow, and with the Special Combo Batarang ability, the Batarangs would explode on impact and floor enemies for longer, even enemies with shields. Each regular Batarang added 1 combo multiplier and then 10 points per multiplier in the current combo meter; in Knight, however, the points are added before the multipliers for Batman and Azrael, who could use the Multi-Batarang, and after for Batgirl, who could not. With the Special Combo Multi-Takedown, Batman would take out multiple floored enemies at once by unleash multiple Batarangs.

Behind the Scenes

 * The original concept of the Batarang was developed by and first appeared in Detective Comics #31 (September 1939). The items have since become a staple of Batman's arsenal, and appeared in every major Batman television and movie adaptation to date.
 * Following the backlash against the campy Batman television series, the franchise has avoided the overuse of the "bat-" prefix, other than the Batcave, Batsuit and Batmobile. Though shown prominently, the Batarangs were very rarely referred to by name.
 * Though they were named after boomerangs, Batarangs became more and more like Shuriken through time. The earliest depictions were of scalloped, metal boomerangs which were used to attack opponents and returned to the thrower. Variations of Batarangs included those which were able to be opened and closed (presumably so that they could fit into Batman's Utility Belt), those which could be explosively charged and those which were electrified. A grappling hook made out of a Batarang and a rope was common until Batman began using an upgraded grappling hook device.

Trivia

 * The item's name is a portmanteau of "Bat" and "Boomerang", and were sometimes referred to as Batarangs.
 * In movie adaptations and some games of Batman, the Batarangs shown matched the Bat-logo of the respective movie/game franchise. The Arkham videogame franchise was no exception.
 * The Batarang was an obtainable item at the Xbox Avatar Marketplace. The item cost 320 Microsoft Points.
 * In Batman: Arkham City and Batman: Arkham Knight, Robin and Nightwing used Shuriken and Wing-Dings much in the same way as Batman used Batarangs.
 * In the Arkhamverse, the Batarangs were collapsible, which made them resemble the Batman Begins Batarangs.
 * After Batman was unmasked, thugs made fun of the Batarangs and called them Waynerangs.
 * This is one of the only five gadgets to be in every Arkham game to date; other gadgets are the explosive gel, the line launcher, the batclaw, and the remote control batarang.