Joe Chill

"You see that kid? That's what happens when you try and be a hero!"

- Joe to a young Bruce Wayne

Joe Chill was a robber better known as the killer of Thomas and Martha Wayne during an attempt to take their money and jewelry in Crime Alley. This traumatic event caused young Bruce Wayne to become the vigilante known as Batman.

Before Arkham Origins Incident
Joe Chill was a lowly mugger who attacked the Wayne family one night on their way home from the Monarch Theatre. Although Chill only wanted their money and jewelry, things quickly escalated out of control when Thomas Wayne tried to fight him.

This ended when Chill shot both Thomas and Martha Wayne dead before he vanished into the night, and left their son Bruce alive, although not before taunting the boy by claiming that trying to be a hero would get one killed. Chill's actions haunted Bruce for the rest of his life and ultimately put him on the path to becoming the city's savior: Batman.

Arkham Origins Incident
Joe Chill was seen physically shooting Thomas and Martha Wayne in front of Bruce during a flashback in the Batcave after he returned from the Royal Hotel, with it also being implied that Batman mentally compared the sheer level of the Joker's depravity as being similar to Chill. He was also indirectly mentioned in the final casefile mission Crime Alley Shootings, where Batman noticed the similarities between the deaths of Clarissa Rodriguez and Horace Riley and the murder of his parents, and it was implied he nearly killed Ian Chase due to projecting Chill onto him.

Arkham Asylum Incident
Chill's voice was heard in the second Scarecrow Nightmare when Bruce relived the death of his parents after being dosed with Fear Toxin.

Arkham City Incident
While Chill didn't make an appearance, Crime Alley did as part of Arkham City; people may have presumed that Bruce's stepping up in his public persona was due to the site of his parents' murders being included as part of the makeshift prison.

Arkham VR Incident
During a Joker Infection-induced nightmare Batman suddenly found himself back in Arkham Asylum; Chill was listed on a clipboard for recording patient names, but after getting to his cell was greeted by Joker instead.

Arkham Knight Incident
Like before, Chill didn't make an appearance, but he was briefly alluded to when several Joker hallucinations, while goading Batman into using a "gun" on Scarecrow stated he was no different than Chill.

Trivia

 * Oddly, when Batman hallucinates the memory of Chill's voice in the first game, it was implied his father ended up being shot regardless of whether or not he complied.
 * In a way, Joe Chill was responsible for every event in the Arkham Series, as he unknowingly and indirectly created Batman.
 * It is unknown what happened to Joe Chill as he has seemed to disappear after killing the Waynes.
 * Nobody but the players know the identity of the Wayne's killer.
 * Batman has most likely been searching for his parent's killer ever since he donned the cowl. But it seems as though he has had no success.
 * Joe Chill was referenced in the achievement for the remastered Crime Alley challenge map in Arkham Knight, as the achievement is called "The Chill in the Air".