Ace the Bat-Hound

Ace the Bat-Hound is a fictional superhero dog appearing in American comic books published by DC Comics, commonly as the canine crime-fighting partner of Batman and Robin.
Publication history.
Ace debuted in "Batman" #92 (cover-dated July 1955) and was created by Bill Finger and Sheldon Moldoff. Ace's introduction followed on Krypto the Superdog's debut in "Adventure Comics" #210 (March 1955), and by German Shepherd Dogs from detective films and serials, such as Rin Tin Tin and Ace the Wonder Dog.
Ace, along with Batwoman, Batgirl and Bat-Mite, retired from the comic in 1964, when editor Julius Schwartz instituted a "New Look" Batman that shed some of the sillier elements in the series.
Fictional character biography.
Pre-"Crisis".
Ace was a German Shepherd Dog originally owned by an engraver named John Wilker. He was found by Batman and Robin after his master was kidnapped by a gang of counterfeiters. Batman used Ace to try to locate Wilker. Because he had already placed a large number of "lost dog" announcements for Ace in his civilian identity of Bruce Wayne, he was concerned that anyone recognizing Ace (who had a prominent star-shaped marking on his forehead) might make the connection between Bruce Wayne and Batman. To forestall that problem, he hastily improvised a hood-like mask for the dog that incorporated the bat-emblem as a dog tag dangling from Ace's collar. Ace was subsequently christened the Bat-Hound by a criminal that the dog helped Batman to apprehend.
Wilker later took a new job that made it difficult for him to take care of Ace, so he left the dog to Bruce Wayne. Wilker was never aware that Ace was the Bat-Hound or that Bruce Wayne was Batman.
An early case involved Ace tracking down a mentally unhinged ancient weapons expert who was using his own weapons to commit crimes. At one point, Ace acquired superpowers thanks to Bat-Mite, but this was short-lived. He did have his own training. For example; his specialized radio collar, when activated, told him to don his own mask (via a hands-free device) and track down Batman and Robin. Ace was used less and less over time, and for various reasons. When Bruce was overcome with night terrors, Robin suggested that Ace sleep beside him.
Ace disappeared from the "Batman" comics after Julius Schwartz took over as editor in 1964. His last appearance was a cameo in a story where Batman had lost his fighting spirit.
Post-"Crisis".
A version of Ace is seen in the cosmic realm of Limbo when the hero Animal Man takes a trip through it.
A modern-day version of Ace was reintroduced in "Batman" #462 (June 1991), although he has been rarely seen in recent years. This version was originally a guide dog belonging to a blind Native American named Black Wolf, who called him "Dog". The dog assisted Batman in fighting criminals from Black Wolf's tribe. Following Black Wolf's death, Batman adopted Dog, renaming him Ace.
He did not wear a mask, nor was he ever referred to as Bat-Hound, and has the appearance of an English Mastiff with a bat-shaped dark patch on his flank. Ace has at times helped Batman on cases and is depicted to be very affectionate towards his owner and vice versa.
After Batman is disabled by the villain Bane, Azrael takes over the identity and ejects Ace, Nightwing, Robin and Harold Allnut from the Batcaves. Harold, a trusted confidante of Batman, takes in Ace; they live in a part of the caverns that Azrael is unfamiliar with. To keep busy, Ace enjoys playing with a robotic mouse built by Harold.
Ace disappeared without explanation after the events of the "No Man's Land" storyline in the late 1990s. He cameos in "".
A traditional Ace was seen in "Final Crisis: Superman Beyond 3D". He is in Limbo with other "forgotten characters", such as Gunfire, Geist, Hardhat of the Demolition Team and Merryman of the Inferior Five. Merryman explains that everyone is here where no stories exist, because nobody is writing about them. Despite this, Superman and his allies work to rescue all the residents of Limbo, who then assist in the battle against the cosmic threat of Mandrakk.
The original Ace appeared in a flashback scene in "Batman Inc." #4, thus making the current canon status of the Post-"Crisis" Ace unclear. In this story, Ace is trying to play with Robin, who is fuming over Kathy Kane, a.k.a. Batwoman, and her influence on Batman.
"The New 52".
In "Batman and Robin Vol. 1: Born to Kill", as part of "The New 52" (a 2011 reboot of the DC Comics universe), Bruce is seen purchasing a black Great Dane from a kennel. He later gives this dog to his son, Damian, who names him Titus, though writer Peter Tomasi stated in an interview that he considered naming the dog Ace. Damian rejects the dog at first, but eventually bonds with him.
"DC Rebirth".
In "DC Rebirth", a different Ace was introduced in "Batman Annual" (vol. 3) #1, in which he is depicted as a former guard dog of the Joker who fought Batman until Joker left him and the other dogs without food in a ditch to fight amongst themselves. The dogs had card symbols on them, and the brown dog with an ace on it killed the others. He was sent to the Gotham Pound, and Alfred adopted him two days later. In order to facilitate this, Alfred actually purchases the Gotham Pound, turning it into the Martha and Thomas Wayne Humane Society. Alfred spends the next couple of months training the dog despite Bruce's objections, as he thinks Ace's wounds from the Joker's actions cannot be healed. Despite this, Alfred manages to properly train him in time for Christmas, and Bruce starts bonding with the dog after getting injured during one of his night shifts. He gets Ace a bat-mask for Christmas and calls him a "Bat Hound". Though the Gotham Pound owner described Ace as a female, Bruce and Alfred have called Ace a him, leaving the gender ambiguous.
Ace is seen later, playing with visitors. He again obeys Alfred without question.
Titus is seen as a pet living in Wayne Manor. It alerts Alfred of Duke Thomas's sneaking out. Titus and Ace are later shown sleeping in twin baskets, confirming that both dogs now exist in the same continuity.
Much like the TV show "Batman Beyond", a Great Dane named Ace is shown to have been owned by Bruce in his old age.
Other versions.
In Mark Waid's and Alex Ross's "Kingdom Come" miniseries, Ace is portrayed as the giant winged steed of the Fourth World Batwoman. Ace is also mentioned in Howard Chaykin's "Elseworlds" crossover '. During a seance attended by Bruce Wayne and mystic debunker Harry Houdini, Ace was referred to as Bruce Wayne's childhood pet. In the "Elseworlds" Frankenstein pastiche ', Dr. Bruce Wayne tests his theories by creating a literal Bat-Hound: a dog with some of the attributes of a bat. A version of Ace appears in multiple issues of "Tiny Titans", a comic created for younger readers. Ace appears in the alternate universe 'Unkillables' storyline, assisting Jason Todd.
Pre-"Crisis", Superman's Batman-like identity of Nightwing included a Kandorian counterpart to Ace the Bat-Hound, a telepathic dog named "Nighthound".