Batgirl/Arkham Knight

Basic Attacks
All of Batgirl's basic attacks execute quickly and deal decent damage. Her 2-hit combo ender deals approximately 4% of her damage stat and gives her better synergy with Overpowered 5-U-93-R and the Gloves of Azrael. Interestingly enough, each hit of her 3-hit heavy combo deals 5% of her damage stat as opposed to the typical 4% damage. All the stated qualities make Batgirl a formidable fighter.

Passive
When an Arkham character is first dealt a knockout blow, Batgirl tags in instead, dealing 10% of her damage stat and stunning the opponent, leaving her teammate tagged out and at 1 health. It can trigger even in the middle of a multi-hit special, during which the rescue will interrupt it in a similar manner as The Flash/Elseworld. Her synergy with the Cloak of Destiny is stronger than ever, as she can stun in multiple ways (both specials, on rescue and on tag-in which is given by the Cloak of Destiny) as well as her rescue having the possibility to crit and counting as a tag-in (meaning the opponent can be stunned before the bomb is even thrown due to the stun on tag-in effect from the Cloak of Destiny). Additionally, she has the highest base damage of all other Batgirl characters in the game.

The hit that triggers her passive cannot apply Area Effect. This makes her very effective against the likes of Bane/Luchador, whose single-hit Rage Slam can devastate entire teams if he first uses his passive to stun the opponent while equipped with the Cloak of Destiny and the League Of Assassins Adept Knives.

Good With

 * Any Arkham characters.

Good Against

 * Doomsday/Prime: Her rescue can prevent him from knocking out Arkham teammates. Therefore, he does not gain any health.
 * Ares/Prime: His powerful SP2 can one-shot opponents and deal Area Effect damage when equipped with his signature gear, which can be prevented by Batgirl.
 * Bane/Luchador: When equipped with the League Of Assassins Adept Knives, he cannot apply area damage to the opposing team following his single-hit SP1 if the hit would KO his opponent.
 * Green Lantern/Red Son: Batgirl has the unique ability to still STUN Green Lantern and his Red Son comrades with her SP1 which makes her a greater threat when equipped with the Cloak of Destiny (X% more damage against STUNNED opponents). (Note: Green Lantern will still have CRIT immunity)

Countered By

 * Green Lantern/Red Son: He and other Red Son teammates are immune to stun and takes less damage from special attacks, dampening her effectiveness.
 * Superman/Blackest Night: The immunity to unblockable attacks makes Blackest Night teammates able to negate the stun by blocking without any consequences.
 * Raven/Prime: A rather unorthodox situation but if Batgirl saves an Arkham teammate and does damage to Raven at the right threshold, she can steal most of Batgirl's health and there's not much the opposing team can do to stop it as Batgirl's tag-in rescue is automatic.

Abilities
Here are Batgirl's abilities.

Support Cards and Gear
Here are Batgirl's support cards and gear.

Trivia

 * Her artifacts are Mask, Gloves, Batarang, Belt and Boots.
 * Batgirl/Arkham Knight is the most expensive directly-promotable character, tied with Deadshot/Suicide Squad, Killer Croc/Arkham, and Superman/New 52 at 495,000 Credits.
 * Currently, both her SP1 and SP2 is bugged where she may perform a knee kick in place of the following hits if the opponent is out of hitbox range, leaving the camera at mid-special angle and in the case of her SP1, her opponent stunned.
 * It is possible for the last hit of her SP2 to miss if it doesn't connect, hence it won't stun the opponent as it it would have.