Mr. Pickles

Mr. Pickles is an evil, demonic, aggressive and bloodthirsty border collie and the titular protagonist villain of the Adult Swim animated series of the same name. Originally a normal dog being used as sacrifice by the ancient civilization of Pavanatra Sluganotharat, Mr Pickles somehow gained demonic power when he was about to be sacrificed by unknown divine entity.

Appearance
Visually, Mr. Pickles very authentically mimics a normal male dog, easily feigning innocence in the eyes of the townsfolk of Old Town, up to the point where he is praised for solving the cases of his own crimes. In reality, however, he is a demonic being. It is possible that Mr. Pickles's true form is different from his canine coil. Before he becomes a demon and during his previous life as a normal dog, Mr Pickles had yellow fur rather than black fur.

Personality
Mr. Pickles is quite wicked, sadistic, nefarious, manipulative, and prone to violence: he seems to be aroused by killing and imprisoning human beings in his secret lair that lies within his dog house. However, despite his dangerous and evil nature, Mr. Pickles is extremely loyal and protective of his human boy, Tommy; this often leads to Mr. Pickles killing or mutilating those who bully or harass the boy. He also seems to have a sense of justice, as he kills a man site for avoiding him to raise an Indian camp where lives a family.

Mr. Pickles appears to only hunt down people with corrupted souls or having considerable sins weighing on their conscience; he also torments Tommy's grandfather but is doing it in a relatively compassionate and merciful manner, only humiliating him (while other victims are usually physically mutilated). The hellhound shows quite a lot of creativity in the tortures, adapting the punishment to the sins of the victim (an example of this would be when he ripped out a young man's stomach and intestine because he forced his girlfriend to have an abortion).

Mr. Pickles is also extremely lustful, salacious, concupiscent, and provocative, so he satisfies his sexual desires with virtually any living thing (and some corpses too), regardless of its size, gender, species or beliefs. He also likes to smell gas, drinks alcohol, and often makes his victims worship him and perform heavy physical work. Severed body parts are sometimes used to build grisly and horrendous trophies. Another passion, giving Mr. Pickles his name, is love for salted pickles.

Powers and Abilities
So far, Mr. Pickles has demonstrated the following powers:
 * Immense physical strength
 * Cunning and sharp intellect
 * Ability to speak in demon language, which causes other animals to obey him without question (with the exception of Dear Boy and snakes).
 * Greatly amplified injuries from even the slightest scratch or bite, such as tearing off someone's face with a mere touch.
 * Sharpened senses, way more powerful than those of a normal dog.
 * Opposable Thumbs
 * Skilled in murdering anyone, even weaponized shoes.

Weakness
However, despite his seeming invulnerability, Mr. Pickles also had at least one known weakness: sensitivity to vacuum cleaner noise. He managed to overcome that weakness by enjoying masturbating with the vacuum cleaner.

Despite Pickles' demonic powers and intelligence, he is still being outsmarted by someone who knows him very well, in this case, is Grandpa. When Pickles tries to kill Grandpa, he manages to outwit Pickles and escape to live another day to fight back him. His arrogance also makes him to let his guard down as Grandpa manages to punch and stun him while he laughs at Grandpa after framing him for murder.

Even though he seems like a demon, Mr. Pickles shows clear signs that he can die by serious situations. (Such as when he was trapped in a snake putt, he couldn't control them so he was in danger or when Grandpa points a shotgun at him while trapping him in the cage, Mr Pickles shows clear sign of fear and panic)

Villainous Acts

 * Opening Sequence - He jumps above two cars, causing the death of the drivers with a car crash.
 * Tommy's Big Job - Mr. Pickles snatches the nipples of a gay man and throw him off a cliff. Later, he kidnaps Grandpa Henry and kill many gays, and plays with their heads. Later, he kidnaps the surgeon that make a pair of breasts to Tommy Goodman and makes anal sex with his horse. After this, he killed Lurlene and the owner of the Jiggly Wiggly. After this, he introduced Grandpa Henry in Betty's ass. Finally, he makes six breasts to the surgeon that make a pair of the breast to Tommy and kills him.
 * Father's Day Pie - Mr. Pickles kidnaps a construction worker and locks him in his secret lair. After this, he took the breasts of Beverly Goodman for annoying Grandpa Henry. Later, Pickles robs a store, killing many of the employees and security guards; also, he cuts the cables of the surveillance cameras. Later, he kills two bosses of the Gabagoolie Mob, and impute the father of the Boss of Stanley Goodman, but leaves alive the principal boss, for make him his slave. Finally, he returns to the store (that was closed) and robs many pickles.
 * Foul Ball - He decapitates a construction worker with a shovel, and puts his head among other heads of his victims, and covers them with dust. Later, his smells Beverly Goodman's butt for annoying Grandpa Henry. After this, he tried two kills with an ax a couple of lesbians in the Baseball Stadium, but this action ridicules Grandpa Goodman. Later, with his demonic powers, he forces a fierce dog to commit suicide by jumping off the balcony of the stadium. After this, he locks Grandpa in the Steam Room of the stadium and put the Steam Control in "Hot". Later, he kills with an emergency ax two cocaine addicts. Later, with a fan mask and the emergency ax, he decapitates the Baseball Collector for rob the baseball ball to Tommy Goodman. And finally, he forces Grandpa to run naked over the field of the stadium, causing his arrest. After this, he robs a box of peanuts (he put inside the ball of Tommy) from an unknown store.
 * The Cheeseman - He kills the pervert Fisherman with a fish hook. After this, he took Beverly Goodman's butt and impute Grandpa. Later, he kills many of the Adolescents Campers in the camping zone. And finally, he cuts the telephone line of the camping zone.
 * Dead Man's Curve - Mr. Pickles kills many peoples and uses their cut faces for scare Grandpa. After this, he tried to kill a paramedic with a scalpel. After this, he kills a pizza deliver snatching his face with his mouth. Using his demonic powers, he forces an army of rats kills a salesman of Old Town. Finally, after overcoming his fear to Grandpa's hoover, he makes love with the hoover very excited (implying that he has object sexuality), with all of his rats seeing the erotic scene.
 * Loose Tooth - He blinds the eye of a man shoving a lollipop inside. Later, with his demonic powers, forces an army of ravens steal the dentures of Grandpa. Later, he blinds the other eye of the man that he blinded at the beginning of the episode. Later, he kidnaps Grandpa and kills many pedophiles that tried to rape Tommy Goodman and uses some parts of their corpses as a human disguise (also, he tortures some corpses for obtaining human blood and sell them to a blood bank). Finally, he kidnaps again Grandpa and puts him as the new scarecrow of a farm and puts dolls' heads in the corpses of the Ravens, which defecate on Grandpa, forming a satanic symbol.
 * Grandpa's Night Out - Mr. Pickles embeds a branch in the ass of a man, killing him. Later, he kidnaps a bodybuilder for make him his prisoner. Later, he snatches the heart of a suitor who tried to flirt with Beverly Goodman. Later, he kills a sniper shoving his rifle in his eye, because he tried to kill the Goodman's, and inmates Ron Bolton of his murder with a photo in a phone, leading to his arrest.
 * Mental Asylum - Mr. Pickles kills the Mayor of Old Town in one of his acts of senseless violence. Later, he guts the mayor and wears his flesh like a suit to impersonate the mayor. Later at a press conference, he disguised as the mayor humps the Mayor's Wife's pet poodle to get the mayor institutionalized to rescue Grandpa. Later, he uses parts of corpses to transform one of the patients of the asylum him into a frog (off-screen). Finally, he kidnaps Warden and reveals the patient who was transformed into a frog to give Warden a lobotomy (which was what Warden wanted to do throughout the episode to his patients).
 * Season 3 Finale - He frames Grandpa for murder.

Heroic Acts

 * Dead Man's Curve - Commanding rats bite off seatbelt to free old man from a car.
 * Loose Tooth - Planting a lollipop into a pedophile's eye to prevent him from raping a child. Making ravens leave a scarecrow to prevent a depressive farmer from killing himself. Killing many pedophiles that tried to rape Tommy.
 * Grandpa's Night Out - Saving Linda from being killed by a hitman.
 * Coma - Killing two men who were diverging a medical hazard in the river.
 * Helping and saving Tommy on several occasions.
 * Mental Asylum - Impersonating the mayor and causes him to have sex with the Mayor's Wife's pet poodle to get him into the mental asylum to rescue Grandpa. However, he most likely did this just so he could continue to harass and torment him.
 * Serial Killers - Killing The Strangler to save Sheriff’s life. Killing Poison who try to poison Mr. BoJenkins. Replacing The Cannibal's toothbrush shiv with a stolen packet of gum to prevent him from attacking.
 * Momma's Boy - Killing the big black wolf that tries to kill Sheriff and Mr. BoJenkins.

Trivia

 * Mr. Pickles' demon language is actually a heavily distorted English speech, played backward so quickly that it cannot be recognized without sound processing. For example, when he commands goats to obey him, he says: "Nice weather we're having. Oh, by the way, I am your master now!".
 * Mr. Pickles shares similarities with Max from the film Man's Best Friend. Both are killer canines who seek vengeance on anyone who abuse them and both are protective of their owners.
 * Despite hoarding/altering several humans to keep as his pets and minions, it appears he may keep a few humans unaltered and uncorrupted as long as it benefits himself. The only example so far is a tap dancing teacher with no signs of mutilation or corruption who taught him how to dance, though this later committed suicide in front of Grandpa.
 * Mr. Pickles may have been inspired by Labby, another demon dog from a piece of critically panned and controversial animation.
 * Interestingly enough, in the YouTube animated series Happy Tree Friends also has a character with the same name as Mr. Pickles, both characters are violently murderous and make a character (the only one aware of both their evil natures) seem insane when they try to prove their evil nature.
 * So far, only Henry Gobbleblobber (Grandpa) manages to come close of killing him.
 * In season 3 finale, Mr. Pickles nearly reveals the detail of his past life in which he used to a sacrificial lamb for the god in ancient time. However, before he can tell more detail. That dog in ancient time was probably his ancestor.