Krypto the Superdog was one of the most surprising additions to the cast of DC Universe's Titans. Indeed, many fans missed the character's first appearance, which came in a post-credits scene hidden at the end of the show's season 1 finale.

Despite having appeared sporadically in the modern DC Comics' universe, Krypto the Superdog is more popular than ever. He's one of the stars of the DC Super Pets book series for young readers, which is being adapted into a feature length film scheduled for release in 2022. Krypto also had his own animated series on Cartoon Network for two seasons, which is still fondly remembered over a decade after its original release.

Related: Titans: Superboy Actor Teases Krypto the Dog’s Return In Season 2

Despite being a mainstay in animated series based on the Superman mythology, Krypto had never been depicted in a manner accurate to the comics in a live-action series until Titans. While a season 4 episode of Smallville did bear the title "Krypto," the action of the episode centered around a LuthorCorp test animal who acquired super-strength after being exposed to Kryptonite. This dog was eventually named Shelby and never seen again in later episodes. By contrast, the Krypto on Titans seems set to stay for a long time. Here's everything you need to know about the Mutt of Steel.

Krypto's Comic History Explained

Krypto DC Comics

Krypto the Superdog first appeared in Adventure Comics #210 in March 1955, in the story "The Super-Dog From Krypton." The story saw Superboy investigating reports of a strange stray dog on the loose in Smallville, breaking through the side of the dog-catcher's truck and stopping a robbery. He was astonished to find the dog, chewing on the robber's gun like it was a bone, before flying off into the sky.

Superboy gave chase and was perplexed when the dog seemed to know him and began licking him like he was an old friend. Eventually the dog led Superboy to the site of a downed rocket of Kryptonian design. A log book inside the spaceship detailed the efforts of one of Krypton's scientists to design a rocket capable of transporting his people away from their doomed planet and how a shortage of test animals forced him to use his family's beloved puppy, Krypto, in one of his final experiments. Even before he saw the scientist's signature, Superboy deduced the unlikely truth; the scientist who wrote the log was his father, Jor-El, and Krypto liked Superboy because he recognized the scent of the infant boy he played with as a puppy.

At first Superboy was overjoyed to have a dog that could keep up with him, but it soon became apparent that a superdog came with a number of unique problems. This was due to the fact that while Krypto was far smarter than the average Earth dog, he was still a dog and had all of a dog's natural urges. While other dogs would chase cars, Krypto chased airplanes - and was more than capable of catching them!

Krypto the Superdog Superman Pet Sidekick

Despite his best efforts, Superboy couldn't keep Krypto on a short leash and was forced to let him roam free. Yet Krypto always came home to Smallville, where he played the part of the Kent family's dog, Skip, when he wasn't helping Superboy or having his own adventures. Krypto served with distinction on two different teams of superpowered animals; the Legion of Super Pets (which was made up of the pets of the Legion of Superheroes) and the Space Canine Patrol Agents. Krypto would go on to die a hero's death, sacrificing himself to save his master from the Kryptonite Man in "Whatever Happened To The Man Of Tomorrow?" - the comic by Watchmen author Alan Moore, which closed out the pre-Crisis Superman comics.

Related: 15 Superpowers You Didn't Know Kryptonians Had

Krypto would be reintroduced into the modern era of DC Comics in Return to Krypton;  a 2001 Superman storyline which saw Brainiac 13 try to trap Superman in an artificially engineered version of Krypton's past. The false Krypton included a genetically-engineered Kryptonian dog, who followed Superman back to Earth after he escaped the trap. Unlike the pre-Crisis version of Krypto, this superdog did not have his intelligence enhanced by Earth's yellow sun, requiring Superman keep him locked up in the Fortress of Solitude until he managed to get Krypto house-trained.

Yet another version of Krypto would be introduced as part of DC Comics' New 52 revamp. This Krypto was Jor-El's faithful dog, who sacrificed himself to save his owner after Jor-El first tried to save his family from Krypton's destruction by opening a portal to the Phantom Zone. Attacked by inmates attempting to escape the other-worldly prison plane, Krypto drove back the criminals long enough for Jor-El to close the portal, only for Krypto to be drawn into the Phantom Zone as well. He would be rescued years later by Superman and brought to Earth.

Krypto's Powers Explained

Krypto and Superboy meet in Adventure Comics #210

Just as the light of a yellow sun gives Superman powers far beyond those of mortal man, so too is Krypto's physiology enhanced by Earth's sun, making him the best of all good boys. Krypto has the full range of Superman's powers, including super-strength, super-speed, flight, invulnerability, x-ray vision, telescopic vision and enhanced senses. Krypto is more powerful than Superman in those areas where a dog is superior to an ordinary human, such as distinguishing scents or hearing. In the pre-Crisis universe Krypto was also as intelligent as a human, but in the modern comics he is believed to only be as intelligent as an Earth dog, despite seemingly possessing a greater capacity for understanding human speech than most dogs.

Krypto's Background And Powers On Titans

Titans Krypto using Heat Vision

Despite technically first appearing during Titans season 1 in a post-credits scene at the end of "Dick Grayson," Krypto didn't fully appear until Titans' season 2, episode 6, "Conner," It was here that a young man who named himself Conner escaped from the laboratories of Project Cadmus alongside a white dog, whose tags identified him as Krypto. While the events of the episode revealed that Conner was a clone who combined the DNA of Superman and Lex Luthor, nothing was said about the origins of Krypto. It is clear, however, that Krypto is smarter than the average dog and has a number of Kryptonian superpowers, including heat vision.

While it is possible that Cadmus was put in charge of an alien dog, this seems outside their purview as a think-tank focused on genetics. It's also unclear just how Krypto could come to be in Cadmus' custody, when they don't typically deal with the Phantom Zone or spaceships. While it is possible that LexCorp captured Krypto independently and turned him over to Cadmus, this still seems unlikely given Luthor's usual do-it-yourself attitude when it comes to handling all things Kryptonian in most adaptations.

The most likely explanation is that before attempting to create a Kryptonian/human hybrid like Conner, Cadmus attempted to splice Kryptonian genes into other lifeforms as a test run. This resulted in their creating a dog with heat vision and enhanced intelligence as a stepping stone on the road to creating the Superman clone they wanted. Whatever the origins of Krypto, it seems clear that Titans will deliver many more exciting stories detailing the adventures of a Superboy and his dog before season 2 has ended.

More: Who's The Best Superhero Dog: Krypto The Superdog Or Ace The Bat-Hound?

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