A weapon was any object or device that enemies, and occasionally allies, wielded to improve their offensive or defensive capabilities. They ranged from simple objects, like Pipes and Baseball Bats, to firearms and explosives, like Shotguns and Grenades.
While in Asylum, City and Origins, Batman did not use weapons himself, and would integrate some of them into counter-attacks and Takedowns. Batman: Arkham Knight allowed players to pick up weapons from the ground, with the exception of Shields, blades, Stun Batons, and obviously, firearms. Melee weapons provided temporary damage boost and the ability to punch through enemy defenses, but broke after a few uses.
Those were simple Melee Weapons that some enemies used to either increase their attack range or their damage. They could be dodged or removed by disarming the enemy holding them.
Those weapons dealt more damage then normal Melee Weapons and could attack multiple times in a row instead of just once. They could be avoided by performing a Blade Dodge and could be removed by disarming the enemy that held them.
Essentially firearms, those were the most dangerous weapons in a one-on-one fight. There were upgrades that provided additional resistance against them, and in Batman: Arkham City, Batman: Arkham Origins, and also Batman:Arkham Knight they could be jammed with the Disruptor.
Those weapons were used in the following way: an enemy walked up to them, picked them up, turned to face the player, and then threw them. They could be either dodged or countered.
- Gas Canisters
- Fire Extinguishers
- AC Units
- Car Doors
Chemical Weapons were only dangerous if the player made contact with them. Some were lethal obstacles, while others triggered story sequences.