Dukey is Johnny's dog. One of the most notable things about him is that he has the ability to speak. He was a very disgusting dog until Susan and Mary enhanced him by mutating him. Since then, he can both fetch the paper and read it. He is also a master at karate, knows somewhat how to speak Chow Now, play video games and gives great advice. When Johnny, Susan, Mary and Dukey are near a human that does not know Dukey and he (Dukey) talks, the other person usually says "Did that dog just talk?". Or when Dukey is near Johnny's dad, and Dukey talks, he (Johnny's dad) says "Did Dukey just talk?".
He is often the voice of reason to Johnny's insanity, but winds up getting manipulated into supporting Johnny's crazy schemes and adventures (usually because of steak or Johnny tempting him into it). Despite his devotion to Johnny, Dukey frequently expresses deep disdain towards Johnny's less intelligent antics, believing their situation as master and pet is reversed.
His dog habits greatly annoy Johnny's sisters, to which Johnny takes deep delight in. Usually once per episode, when trouble arises and there's no alternative, Dukey will say something along the lines of "Here's an idea: RUN!" Dukey has admitted that he's ticklish and can't resist a belly rub from Johnny.Similar to Johnny's "Johnny X" form, Dukey also has a secret identity which unlike his master he does not particularly enjoy called "Super Pooch", although he is also referred to as "Super Dukey" and "X-Pooch". When in "Super Pooch" form, Dukey can fly and in the Third Season has shape shifting powers, the ability to sense what others are doing, and the ability to teleport. He has the power to fly as a sidekick (to Johnny) but usually crashes when landing. He also likes to drink hot coffee. His favorite food is steak (He likes all kinds of steak, but his favorite is porterhouse seen when Dukey quizzes Johnny and his cyborg clone to see who's the real Johnny.
Super Pooch/Super Dukey
Dukey goes as Super Pooch/Super Dukey (later episodes) when Johnny goes as Johnny X. Dukey claims that he hates becoming Super Pooch in "The Revenge of Johnny X". Also, in "The Destruction of Johnny X" Dukey claims that his Super Pooch costume gives him a mega-wedgie. Dukey isn't as enthusiastic about being a superhero as Johnny is, but he is forced to go along with his schemes on account of reverse psychology, guilt, and offerings of steak.
- Super Strength
- Shape Shifting
- Teleportation (only in "Johnny X: The Final Ending")
- Oral Force-Fields.
- Power poots (sometimes)
- Super Vision
Dukey is a NPC in Fusionfall. He and Johnny are at the Nuclear Power Plant which they think is a skate park. Interestingly, there are two skateparks in the downtown area of the game, one of which (like the Nuclear Power Plant) is an Infected Zone. He is also a shop vendor.
- He also has an allergy (as said in the episode Li'l Johnny), but from what he didn't say although its speculated to be from large dust mites. quote "and they make people and dogs sneeze..."
- Dukey also appears to be able to know exactly what happened in certain situations. For example, when Johnny attempts to catch a cold from Sissy Blakely in order to skip school but gets sent flying out of the house, Dukey says something along the lines of "Didn't get the cold?" even though he was waiting outside Sissy's house at the time.
- Super Pooch's name is later changed to just Super Dukey.
- Dukey's love interest is Sissy's dog Missy, he falls for her in "Saturday Night's Alright for Johnny."
- Dukey has a spot on his butt he can't reach and loves it when someone scratches it.
- Dukey's age might be 11 because the age-swapped Eugene turns both Johnny and Dukey back to their original ages in Johnny vs. Bling-Bling 2.
- Dukey has a distinctve braying laugh which is slightly similar to Orange's in The Annoying Orange series.
- As of Johnny Goes Nuts, Trevor Devall has replaced Louis Chirillo as the voice actor of Dukey. According to IDBM, Chirillo left so he could be with his wife in Brazil. However, sound bits of Chirillo may be used in conjunction with Devall's lines. Chirillo also briefly returned to the role in a bumper for Cartoon Network's 20th Birthday celebration.
- He is one of the two characters to appear in all episodes. The other character is Johnny.
- In It's Du-Kay Johnny, Dukey was turning into a dog and the girls decided to upgrade Dukey's DNA.
- In Johnny Vets Dukey, Dukey is afraid to go to the vet because of the pointy needles, the coffee is cold and the thermometer supposed to go under the tongue.
- Hugh and Lila found out Dukey could talk in Johnny's New BFF.