7eventy 5ive: The killer in is both crazy and uses an axe to kill people.
Alien³: Walter Golic is by far the craziest convict. Even though he didn't kill the two inmates that the others suspect him of having murdered (the Alien did it), he is still a homicidal nutcase. When he's contained in the infirmary in a straight jacket, he turns to Ripley and suddenly reminisces about a few women he knew back home. Then he looks her in the eye and says that she's gonna die too.
American Psycho: Patrick Bateman is a successful stockbroker by day, serial killer by night.
The Avengers: Loki, the main villain, announces his arrival on Earth by killing a bunch of S.H.I.E.L.D. agents with the evil spear of doom that the Chitauri gave him. He then proceeds to kill many more people over the course of the movie.
Barnaby: Item 1: Kidnap Tom. Roderigo: * Makes throat-slitting gesture* Gorganzolo: No, just kidnap him. Barnaby: Item 2: Throw him in the sea. Roderigo: * Repeats gesture* Gorganzolo: No, just throw him in the sea! Barnaby: Item 3: Steal the sheep. Roderigo: * Stabbing motions* Barnaby: No, just steal them!
Bad Boys: Fouchet's plan seemed to involve killing everyone he encountered. His first reaction when the cops arrive at the end? Shoot his partner.
Victor Zsasz from Batman Begins, as is usual in the comics, he is a very insane criminal.
Battle Royale: Kazuo Kiriyama shoots down several unarmed girls, grabs their megaphone and puts it to one girl's mouth so everyone within hearing distance can hear the sounds she makes as she dies.
Caligula: The title charcter. Tiberius also gets a couple of moments.
Tiberius: Do you think this boy has drunk enough wine?
Caligula: I think he's drunk enough, Lord.
Tiberius: So do I! *kills drunk man* Now he is happy.
Blue Velvet: Frank Booth is one of the most memorably profane and sadistic psychopaths ever put to film.
Body Bags: The killer in the first segment is an escaped mental patient who slaughters people because he's either insane or just enjoys murder. Or both.
Cemetery Man. When the Grim Reaper tells you to kill people, you kill people.
Dawn of the Dead: Wooley just runs around the apartment building in the beginning of the movie shooting everybody in sight, whether they were zombified or not. He was so out of control, the SWAT had no choice but to kill him.
The Sandman is a psychotic serial killer who murdered people for fun. Near the climax, he releases all the prisoners from their cells to watch them cause mayhem.
The two cons who worked together with the warden to kill prisoners and silence anyone who might expose seem to be in it more out of sadism than any profit.
The Descent: Sarah turns into this over the course of the movie. Differs from many examples in that it wasn't a random attack so much as the Ax Crazy making her act on her motivations. Alternately, the movie purposely left open the possibility that she had imagined the creatures and it was really just her slaughtering all her friends. Which would make her much more Ax Crazy, and throughout the whole movie. Only in the Revised Ending, though. In the original ending, there's an additional scene which shows her about to be killed by the very-much-not-imaginary creatures while hallucinating that she's back with her dead daughter.
Devil In The Flesh: Debbie is a Yandere who kills numerous people and tries to kill her teacher's wife (she has an intense crush on her teacher).
Django Unchained: While Calvin Candie is a sadistic sociopath, at first, when we know him, seems polite, calm and sophisticated. However, when he learns what Django really wants to do, he has a severe Villainous Breakdown and shows his true violent and psychotic nature with his hammer.
D.O.A.: Chester enjoys hurting people. He especially relishes the gutshot, since it kills people nice...and slow.
A Fistful of Dollars: Ramon Rojo is extremely obsessed with a woman, is widely paranoid, and tortures and kills in cold blood. He is a dangerous psychopath and makes a Slasher Smile during many of their massacres.
For a Few Dollars More: El Indio is even more unstable than Ramon, Indio is a full-blow insane man, especially when he smokes (presumably) marijuana.
Elysium: Kruger is crazy enough that he uses his goddamn katana to cook food with. What makes him one of the most batshit insane villains yet is his horrifying reputation for being a human-rights violator and for having a very bad habit of blowing people up, going as far as calling an injury that he inflicts on those who get in the way "a flesh wound", before blowing them to chunks. And once he finds out Delacourt's "classified info" was a total system reboot for Elysium, he decides to kill Delacourt and get the data himself to turn Elysium into his personal hell.
Gamer: Hackman is a mountainous inmate who enjoys killing way, way too much. Lampshaded when Kable notes that he really isn't right in the head when Hackman comes to boast about killing another prisoner.
Tommy Devito has a Hair-Trigger Temper and kills people for the slightest offense. Made even scarier is the fact that he is based off of a real-life gangster.
Jimmy Conway is a very subtle example. We rarely ever see him lose his cool, and he comes off as a rational individual. Then the corpses of nearly everyone who participated in the Luftansa Heist start popping off everywhere.
Halloween: Michael Myers is really a subversion. He is more calm and quiet that crazy, but still has several features of a true Ax Crazy, he's a cold-blooded homicidal maniac without conscience who enjoys killing.
Inglourious Basterds: Hugo Stiglitz may be one of the good guys, but that doesn't make him any less unnerving: he murdered thirteen Gestapo officers not out of disgust with their crimes but because he's so bloodthirsty himself, and when he smiles, it's really truly creepy.
Jack the Giant Slayer: Wicke comes off as just slightly unhinged during a lot of his screen time. Whenever Roderick gives him the cue to either kill someone or that he's going to do it himself, he reacts with glee and excitement, and even when that's not happening, he's usually trembling and/or smiling eagerly about doing whatever it is they're planning to do next.
A View to a Kill: Max Zorin is really enjoying himself when he is gunning down his employees near the climax.
Quantum of Solace: Dominic Green becomes this towards the end when James ruins his plans and destroys his entire facility, at which point, he completely snaps and uses an actual axe to try and chop Bond into pieces, all while screaming like a complete lunatic.
Elle Driver is a venomous, hateful, Rival Turned Evil who distinguishes herself from the other ruthless killers of the Deadly Viper Assassination Squad by being the only member who is genuinely evil and malicious.
Last Action Hero: Ripper, a fairly generic ax-murderer, is one of the antagonists. The fact that he's a hulking, semicoherent clone of every other Ax Crazy slasher on film is surely deliberate, as he's a fictional character from a rather trite series of lowbrow action flicks.
Lord of War: Andre Baptiste Jr. is known as a cannibal, and he shoots civilians for sport. His father as well, as he callously shoots one of his own men for even looking sideways towards his woman. They're both usually more restrained, though.
Man Bites Dog: Benoit is a completely unpredictable Serial Killer. His crimes are sometimes motivated by money, but they are generally completely random. At his birthday party for example he's ecstatic about trying his presents... and shoots one of the attendees in the head without warning. He then continues enjoying the party like if nothing happened.
Matilda adds a good dose of Ax Crazy to the Trunchbull in addition to her cruel treatment of her students. The first thing she does when she suspects intruders in her house? She bull-charges from room to room, leaps down from the second floor, bringing down her chandelier in the process, and eventually starts swinging an Olympic hammer around and randomly smashing it into her possessions.
The Professional: Detective Norman Stansfield has the habit of murdering families while humming Beethoven, in fits of drug-induced lunacy (though it doesn't help that he is also a death obsessed psychopath).
The Proposition: Arthur Burns is a well read and very deep Warrior Poet...who just happens to have a penchant for gang-rape and mass murder.
Red Eye: Rippner tries to kill Lisa's dad and Lisa and herself during his Villainous Breakdown following Lisa stabbing a pen through his neck.
Repo! The Genetic Opera has Luigi Largo. He's been described as walking around with a flask and a knife, drinking and stabbing anything that gets in his way, including his own employees. He's also tried to strangle his brother in 'Mark It Up'.
I'm the smartest and the toughest! I will find a hole and fuck it! If there ain't one, I will make one! Luigi don't take shit from no one!
The Rocky Horror Picture Show: Never steal Dr. Frank N Furter's spotlight while he's holding a pickaxe. It may be the last thing you do. Meat loaf, anyone? He can also be pretty intimidating with an electric carving knife.
A Room For Romeo Brass: Morrell appears to be just a lonely eccentric, but he soon reveals his true colours when he threatens a disabled boy with a knife for a harmless practical joke that made him appear foolish in front of the woman he is obsessively fixated upon, threatens to kill the boy's family, and then threatens to kill the boy's best friend (and brother of the object of his lust) when the woman rejects him. However, compared to several of the others on this list he's an unusually laughable and ultimately rather pathetic example; his attempt to make good on his threats is put in its place when the best friend's estranged father — who hasn't taken any of Morrell's shit throughout the movie — charges in, gives Morrell a good kicking and sends him skulking away with his tail between his legs and the promise that, if the boy's father ever sets eyes on him again, he'll be the one who ends up dead.
The Salton Sea: Pooh-Bear is both crazy and extremely dangerous. For instance, he nearly castrates the protagonist out of paranoia and because it's amusing to him.
Hannibal Lecter is a cannibalistic serial killer, although a rather polite one. He escapes from his cage bludgeons his captors to death with a cool, detached expression on his face. He's the Villain Protagonist of the sequel, where he actually cuts off his own hand in order to escape at the end. Anthony Hopkins himself would be the first person to tell you that the guy's crazy.
"A census taker once tried to test me. I ate his liver with some fava beans and A Glass of Chianti. *hisses*"
Buffalo Bill tries to build a suit out of the skin of the women he murders.
Single White Female: From the number of people whom Heddy kills and impersonates she certainly seems to fall under the Axe Crazy heading.
Angela Baker: I've never chopped wood before, but I've chopped other things!
Snow White & the Huntsman: Queen Ravenna. Other versions have always been self-centered, vain, and downright cruel, but this version will kill anyone who defies her without a second thought. Plus the implication that she's killed plenty of kings in the past.
Star Trek: Captain Nero wakes up in the morning looking for new shit to blow up. And with advanced tech from the future, he can actually accomplish this. Sometimes he switches it up a little and becomes a Bladed Romulan Sceptre Crazy, instead.
The Stepfather: The eponymous killer, whose sanity is shaky at the best of times, goes from perfect All-American dad to a ranting attacker who beats people to death with a wooden board or stabs them in them in the face with a rake at the drop of a hat.
The Transporter 2: Trigger Happy Lola, the villain's Dragon. "Actually, my problem's not medical. It's psychological." (shoots the nurse.) And a few moments later: "What seems to be the problem?" "Me." (yet another burst of gunfire.)
Versus: The Yakuza with the Green Shirt (Kenji Mastuda) from Kitamura's seems to be utterly and completely unable to be serious or show any signs of normalcy through the movie; he constantly makes faces and sounds, laughs like a maniac, screams and overall draws attention to himself by simply being a nutjob in every scene where he's present.
Who Framed Roger Rabbit: Judge Doom is for the most part, a calm, cool, and collected version. Then after he gets flattened he loses it and tries to kill Eddie in incredibly sadistic ways while letting Toon Town be wiped off the map.