Spoilers for major stories
Batman: Arkham Shadow
ahead.
One of the greatest storytelling elements of the Arkhamverse is that it never spends precious time recalling Bruce Wayne's childhood, at least not in a way that overreacts how his parents were shot in Criminal Alley. The series makes extensive use of the imagery of this tragic and catalytic event, but thankfully it doesn't Arkham the game chose to dig up these details at the expense of any enticing plot set in the present day. However, it is interesting that Bruce apparently never knew what happened to his parents' killer and their whereabouts after that.
Not knowing what happened to Joe Chill worked to the Arkhamverse's advantage, as it was easy enough to write him off as any anonymous criminal whose bones Batman had broken since, allowing him to drown in a sea of petty thugs and further fuel Batman's plight. However, Batman: Arkham Shadow decided to dig up some stones and paint this picture more clearly. U Batman: Arkham ShadowJoe Chillo is revealed, and his role serves as the crux of the narrative, intrinsically tied to Bruce's perception of depravity in Gotham City.

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Batman: Arkham Shadow Review
Batman: Arkham Shadow successfully brings the Arkham experience into the VR space with brutal combat and an immersive atmosphere.
Batman: Arkham Shadow's “Joe” is none other than Joe Chill
Joe Chill's only other physical appearance in the Arkhamverse is through Rocksteady
Batman: Arkham VR
though it's debatable at best whether this hour-plus VR experience is canon at all, and evidence suggests it may be a lingering nightmare that Bruce is living through.
Bruce, as Irving Malone, becomes close to a dealer named Joe Shadow not realizing who this person is he's talking to as he spends a good portion of the game in disguise at Blackgate. Of course, any Batman fan who hears the name “Joe” can instantly put the pieces together, especially when the name is associated with an elderly inmate whose last name is intentionally omitted and whose backstory is unknown.
Joe even develops a sense of empathy as he outwardly apologizes and suffers from his mysterious past. However, Shadow makes it abundantly clear that Batman is blinded by rage and his goal is to find the Rat King at this point, and so the billionaire orphan probably wouldn't have known Joe's identity.
How Joe Chill distills the Batman: Arkham Shadow Theme of Empathy
Joe is a perfect representation Batman: Arkham ShadowMain themes, illustrating that not every criminal is the epitome of evil and that not every classic benefactor is a pure saint. It's understandable why Batman was so violent in Gotham, as his criminal element is known to be very vicious, but how do the RATS, GCPD and TYGER perceive Shadow does a great job of showing how few characters in the Arkhamverse are black and white in their morals or ethics.
Players may have grown accustomed to henchmen being bland punching bags, if not comedic relief. While thugs, of course, keep their sense of humor ShadowThe rats are much more sympathetic in their plight, which in turn shows just how big Batman's blind spot is for them when they target Dr. Leslie Tompkins and District Attorney Harvey Dent.
It's a lesson in empathy that Bruce learned when he realized what happened to turn Dr. Victor Freeze into Mr. Freeze in
Batman: Arkham Origins
' Cold, Cold Heart DLC, and it's a lesson he faced again in the
Shadow
when the lives of his loved ones are at stake.
Batman: Arkham Shadow ends before the dust has a chance to settle
At the end of c Batman: Arkham ShadowHarvey Dent calls Bruce to tell him that he has captured Joe Chill, the man responsible for the death of Bruce's parents. Shortly after, Batman arrives on the scene to find Joe on his knees in front of Harvey/Two-Face, and as Bruce removes his mask in front of them both, he surprisingly tells Joe to leave in a moment of unprecedented warmth.
Joe apologizes to Bruce and Shadow ends rather abruptly after this sequence, offering no real closure as to Joe's whereabouts or how Bruce comes to terms with the information. Bruce is more concerned that Harvey is a mess and confused at this point, and still, it would have been great to see this scene simmer longer, so that any unspoken feelings could be more deeply shared – maybe a job for a sequel. It's entirely possible that Joe will live out the rest of his life rotting in Blackgate, which is why he's never seen again in the series, but the takeaway from this ending is that Bruce has made some semblance of peace with the idea that Joe is never able to forget what happened to his parents.
Batman's goal is the same as always, to protect Gotham City, and whether or not the presence of the likes of the Joker has spawned him, his view of common criminals, as well as the human condition, is likely a bit different after how the murderer of his parents unknowingly encountered him and recognized him as a man.
It would be wonderful to have Bruce reflect on Joe, if nothing else ShadowBatman muses Origins and Blackgateevents. However, if Joe is never spoken of or heard from again, Shadow does a commendable job of conveying how Bruce might perceive him because of the conversations they shared as Joe and Malone, and there are certainly more sinister and menacing figures for him to deal with in his later years as the World's Greatest Detective.