Avengers: Endgame: Thanos suffering from a horrible burn scar on the left of his face, including the loss of an entire ear. This is because he's destroyed the Infinity Stones using their own power, and the power surge has seemingly destroyed the gauntlet and taken Thanos's left side as a result. Later, Tony is shown with the same scar after snapping Thanos and his forces out of existence.
Batman Forever: How Harvey Dent becomes Two-Face. Unlike The Dark Knight iteration, the facial scarring was the result of an acid attack by underworld kingpin Boss Maroni.
Batman: This is also how Jack Napier became The Joker; a combination of being shot through the face and a huge vat of acid (which did wonders to the rest of his body and hair too). Later, he disfigures his girlfriend Alicia by corroding half her face.
Beetlejuice: Barbara's first attempt to frighten off the new tenants of their house. When they open the closet door, she's swinging from a noose - then yanks her face off, leaving a freaky skull with bugged-out eyeballs. Too bad they couldn't see her...
In one scene, when Claire looks at herself in the bathroom mirror, she sees the left side of her face is drooping. She starts pulling on it, causing a cut to appear on her forehead. She then pulls the drooping part off, revealing a while surface covered in cracks underneath. Thankfully, it's a hallucination.
When Claire and Bethany were kids, their mom stitched a mask to Bethany's face
Billy Club (2013): Billy kills Kyle by beating him in the face with the spiky end of his baseball bat. Each hit leaves a bunch of scratch marks all over Kyle's face.
Blood Bags: The killer's face is extremely swollen, and missing its lips.
Blood Pi: Amber kills a cheerleader with a knife In the Back, and then cuts off part of her face to make into a Domino Mask.
Blood Widow: The killer catches Hugh in the face with her cat-o-nine-tails, and then yanks back hard, ripping chunks off his face.
Bloodshot: Among the injuries that Ray takes and regenerates with his Healing Factor are shots that tear the skin off the left side of his face to expose his teeth.
The Burning: Cropsy has a hideously scarred face as a result of a Deadly Prank that set him on fire, and is eventually finished off with an axe to the face.
Cain Hill: While looking about the titular A Bandoned Hospital, one of the crew finds a dead body with lots of lacerations on its face.
Captain America: The First Avenger: When the evil Red Skull peels off his mask to reveal the facial deformity that gave him his name, sidekick Bucky mutters to Cap, "You don't have one of those, do you?"
Carrie (2013): Alpha Bitch Chris Hargensen gets thrown through a windshield when Carrie crashes her car, leaving her face torn up with huge shards of glass sticking out.
The Casino is an excruciatingly violent Shaw Brothers action film, whose highlights include a henchman whose face gets stomped into a red pulp. There is a close-up on his bloodied face, and it's NOT pretty. See for yourself. (WARNING: GRAPHIC GORE ALERT)
A Classic Horror Story: At the cast party, Elisa sees a boy singing a song to the accordion. The right half of the boy's face looks droopy and folded.
Clawed: Expect to see a lot of deformed, mutilated faces in this movie. Sheriff Reynolds has claw marks on his face in the Framing Device.
Clown Kill: The janitor's face has a large red area that looks very wrinkly. It appears to be a healed wound.
Clownface: After stabbing his second on-screen victim, Clownface cuts part of his face off to feed it to Zoe.
Creepshow 2: The hitchhiker from the last segment get run over and has his face smashed by a car against a tree several times, causing his face to be nothing more than a bloody mulch with his eyeballs dangling from their sockets
The Dark (2018): Alex's eyes are both covered by scar tissue, and Mina's face has many gruesome gaping wounds still on it from her rapist bashing her with a snowglobe when she resisted him.
Similarly, how Liam Neeson's character becomes the title character in Darkman. Durant's thugs burn his hands and dip his face in acid before rigging his lab to explode.
Wade Wilson after he gains his powers in Deadpool, which results in his face getting horribly disfigured. He covers it up for most of the film with his outfit's mask, though at the end, Vanessa takes off Wade's mask to reveal a cutout of Hugh Jackman's face hiding his scarred face before that is removed too. All of this even gets lampshaded at one point.
Deep Rising has a scene where one of the pirates is attacked and swallowed by a monster. His comrades manage to shoot him out, only to find to their horror that he'd been partially digested by the acidic innards of the creature. Half of his face and even part of his skull get eaten away, along with most of his body.
Elysium: Krueger's face gets blown off by a grenade during the second half. However, that doesn't kill him.
In Faceless, Ingrid's face is hideously disfigured when one of her brother's former patients throws acid in it. Her brother then surgically mutilates several over beautiful women in attempt to find a cure for her.
The premise of Face/Off, which involves Sean Archer taking Castor Troy's face and voice. Afterward, Archer's original face is left floating in a jar of water to keep it moisturized. Troy wakes from the coma, peels off the bandages in front of a mirror, and is very unhappy with what he sees. We only see a couple of very quick glances that show Troy walking around without his face on, prior to making Dr. Walsh give him Archer's original face.
FairyTale: A True Story: The soldier whom Frances befriends on the train suffered extreme wounds to his face, which for most people must be offputting. She's completely undeterred though, and he thanks her later by chasing off a nasty reporter who'd been harassing her, coming to hear that fairies are real.
Fight Club: The Narrator beats the shit out of Angel Face's... um, face so brutally it's barely recognizably human, and most of his teeth are gone.
The Final: Emily smears flesh-eating chemicals on Bridget and Heather's faces in order to ruin their good looks, as revenge for their bullying Alpha Bitch tendencies. Bridget is seen in the Book Ends as an outcast, wearing a hoodie to hide her disfigured face.
Seth Brundle's face falls off in a slimy mess near the end of The Fly.
The Fly II: A security guard gets a faceful of acid vomit from Brundle's son. The worst part is, he's still breathing afterward.
Over time, the mute colossus Jason Voorhees from Friday the 13th has taken some serious facial damage. Notably, he took a boat motor to the face in part six. It's little wonder he's seldom seen without his trademark hockey mask.
During the third chapter of Friend of the World, a creature attacks the characters and attempts to facially merge with Gore. His nose is briefly duplicated as a result. Moments later, Diane hallucinates from the antidote Gore gave her. When she confronts him about it, his face is disfigured because of the side effects.
Rocco The Clown rips the mask, and face, off a park employee.
When Morgan and Gerardo kill Animal, they do so by pressing his face against a rotating hot dog grill.
In The Gambler, Axel picks a fight with a pimp and the hooker he’s with slashes his face to defend said pimp. Axel actually looks happy about this once he escapes.
Ghost Lab (2021): When Dr Gla's ghost attacks Dr. Wee in the morgue, the latter throws a bottle of mortuary chemical's in the former's face, causing his cheek to fall off.
The eponymous Girl on the Third Floor has a bizarre, mangled face that looks more like ground beef than anything. It's possible that this was the state her body was left in when she was originally killed. There's also the death of Milo, whose left eye is replaced by a gaping hole when Sarah hits him with a hammer and the state of (the fake) Don's face when Liz finds him after attempting to cut the Nymph's marbles out of his body.
The Golden Voyage of Sinbad. In the Backstory, the Grand Vizier of Marabia had his whole head badly scarred by a fireball (think melted wax). He wears a helmet throughout, until near the end when he takes it off to frighten some natives with his hideous face.
Guardians of the Galaxy Vol. 3: Rocket's final flashback shows that when he escaped from the High Evolutionary's lab, he first took revenge on his creator by jumping on top of him and mauling his face. When the High Evolutionary is defeated during the Final Battle, it's revealed that his seemingly healed face is a mask, underneath which his real face is shown to have been Stripped to the Bone by the damage Rocket did all those years ago.
At the end of Halloween: Resurrection, Michael Myers is set on fire and presumed dead. Cue the horrific morgue scene that reveals his mask had melted into his face...and he was still alive.
Hayride 2: Ol' Pitchfork kills one of the hospital orderlies by pressing his head against a scalding hot pipe. In his struggle to escape, the orderly tries to get his face off the pipe, showing that his flesh has melted against the pipe's surface.
Head: Mild example - this is when The Monkees made every effort to distance themselves from their cultivated image. In a parody of boxing movies, preteen heartthrob Davy Jones got his face beaten to a bloody pulp by sparring partner Sonny Liston (think the '60s era Mike Tyson). Intercut into this we see Jones joshing with Liston beforehand, saying "You won't hurt the face, will you? Million-dollar face, this is!"
House of the Witch: Dax gets a wound on his back early on. As time goes on, the wound somehow turns into a large collection of pustules covering half his face.
The Hunger Games: The beautiful tribute, Glimmer, is horribly disfigured after she is stung by trackerjackers. Her face is particularly horrifying in the movie version.
Inglourious Basterds sees the titular Basterds acts of violence against the Nazis involve carving a swastika into the heads of any who survive.
Into the Grizzly Maze: After being attacked by the bear, Douglass shows up with half of his face ripped open and flapping loose.
Irréversible: An infamous scene where a man caves in another man's face with a fire extinguisher. Poor Alex also has her face beaten and mangled so badly that she will never be beautiful again.
I Spit on Your Grave: Jennifer gets revenge on one of her rapists via putting lye in the tub of water she has him suspended over. His face falls in when he can't hold the position anymore and his face burns and melts off including his tongue.
Jonah Hex (2010): The film version depicted a more pragmatic version of this, as (which Krimson Rogue rightfully pointed out), no one's willing to lose their right cheek for a part and the movie didn't have the budget to do a motion capture effect and opted to use make-up.
In The Last Rites of Ransom Pride, Maria La Morena is a beautiful woman with hideous burn scars across one side of her face.
Let the Right One In: Håkan pours acid over his own face as an attempt to become unidentifiable to the police. He lives, and the effect is horrifying.
Mirrors features a fatal and extremely gruesome jaw dislocation scene.
The Monster Maker: Lawrence's face becomes hideously distorted by the acromegaly Dr. Markoff infects him with. Acromegaly causes distortion of the extremities (hands, feet, and face), and the version created by Markoff causes to Lawrence to advance in a week to a state that would normally take two years of the disease's progression. Glimpsing her father's face in a darkened room causes Patricia to scream and faint.
Murder Party: Macon tries to light a cigarette while wearing a rubber or latex wolf mask, which naturally catches ablaze. His friend Lexi and the photo assistant of his friend Paul manage to put the fire out, but not before it horribly disfigures him, fusing much of the mask to his face. He remains like this until he dies, though that isn't very much later.
In Murders in the Rue Morgue (1971), Marot's face was hideously disfigured by acid, and that is now how he murders all of his victims.
House of Wax (2005): Vincent wears a wax mask to hide a whole section of his face missing from when he was separated from his brother Bo, joined at the back of the latter's head.
Freddy Krueger, the iconic dream demon from A Nightmare on Elm Street, has extensive burns all over his body, the result of the parents of Elm Street taking the law into their own hands during his days as the Springwood Slasher.
Nobody Sleeps in the Woods Tonight: The killer twins' bodies have boils covering their bodies. This is likely the result of the twins being host to a black alien slime that came out of a space rock they hid under their bed. The highest concentration of boils seems to be on the twins' faces, and feet.
In the sequel, when Zosia kills Wanessa, one of the first things she does is tear all the skin off her face.
Nope: A chimp goes crazy at a filming of a sitcom. One of the survivors of the attack, Mary Jo Elliot, had her face mauled by the chimp.
Another Shaw Brothers film, Oath Of Death, sees Jin Liang, the main character, being betrayed by his older sworn brother and becoming a wanted man. In order to evade authorities, he's forced to put a burning hot sword upon the left side of his face, and the aftermath isn't pretty at all.
One Night in October: At the climax of Michelle's story, when she has Jason in her garage, she reveals to him that she sliced all the skin off Hewitt's face.
The Orphanage: The fake social worker gets hit by a bus, and you can see her lower jaw completely unhinged, hanging off from her face. Even worse, before the face is fully shown the main character's husband tries giving her CPR.
Ironically, her face ended up worse than her son's Tomas, who was forced by her, because of his disfigured features, to wear an actually much more unsettling scarecrow mask.
One of the most well-known images of Overlord is its main antagonist Wafner missing most of his left cheek while sporting a Slasher Smile, after having been shot in the face about two-thirds through the film and taken the serum to save his life.
Pacific Rim: One of the Kaiju gets subjected to a dose of this during a deep-sea battle, thanks to a conveniently placed hydrothermal vent. Not enough to kill, but the thing had a lot less face by the time it broke free.
A similar scene in Pan's Labyrinth, except with the bottom of a bottle of wine. And later on, the villain is given half a Glasgow Grin with a kitchen knife which gives him some trouble with enjoying whiskey afterwards.
The 1943 version introduced the idea of the Phantom having not been born disfigured. In that adaptation, he was a normal-looking man until he was scarred by acid.
In the tradition of the 1943 version, the title character of the 1962Hammer Horror adaption was an ordinary man disfigured by acid. However, they take his facial injuries even further with one of his eyes having dissolved and his flesh slowly rotting and turning grey.
The Phantom in the 1989 version has no skin around his head at all, and his "mask" is a patchwork of skin that he has taken from his victims.
After the eponymous Phantom of the Paradisedestroys the videotapes and contracts keeping Swan, Phoenix and himself immortal, Swan’s face begins to rapidly putrefy before he is stabbed to death.
Pirates of the Caribbean: Dead Man's Chest: Will Turner is searching a shipwreck for survivors when a man falls from aloft. Will helps the guy turn over, only to recoil in horror when he sees that his face is a twitching mass of sloughed-off skin and one moving eyeball due to an encounter with the giant suckers on the Kraken's tentacles.
The Raid 2: Berandal: One mook who attacks Rama gets the side of his face pressed against a hot stove, leaving the mook severely burned.
[REC]: Alex has extremely nasty and gruesome bite wounds on his face after encountering Mrs. Izquierdo.
Red Mist: Sean suffers arguably the most horrific death - having a funnel forcefully shoved into his mouth, duct-taped to his face... and industrial-strength acid poured into it. After his corpse is discovered, it is mentioned that half of his face had practically melted off.
Repo! The Genetic Opera: It's revealed that Amber Sweet's face is horrifically scarred from repeated low-quality surgeries. Rotti gets her a transplant, but during the climax, her transplanted face falls off during her performance at the titular Genetic Opera, and she storms off the stage in embarrassment.
In the American adaptation of The Ring, Noah's face is horribly distorted and shown in close-up after Samara killed him.
Rush: Niki Lauda's horrific burns after being pulled out of his burning car during the German Grand Prix where his helmet was knocked off and the Nomex sock he wore was not enough to protect his face.
The Reverse Bear Trap does this to any victim who doesn't break out of it, ripping their lower jaw off completely. Although it's seen repeatedly on various characters, it's not until Saw 3D when the actual result of someone dying with it on is shown.
In Saw IV, Cecil's face ends up being caked in blood after going through the Knife Chair, a trap that requires its victim to press their face against a contraption of multiple knifes.
Se7en: The Pride victim is a model whose face has been mutilated by Doe; she was given the option to call for help and live disfigured, or commit suicide by taking pills.
Skyfall: The villain looks pretty normal, until he's captured and confronted by his former boss, M, who sold him out to the Chinese. He explains how he was tortured for months before attempting to commit suicide via the Cyanide Pill in his back molar. It didn't work. What it did instead is revealed when he removes a prosthetic from his mouth and the left side of his face just sags inwards.
Darth Vader. Yeah, you probably don't want to see what's behind that mask...
His master Palpatine had the face of a kindly old man during his time as Chancellor. Then his own Force Lightning quite literally blew up in his face, leaving him permanently disfigured. His eyes also permanently turned glowing yellow, making them look much bigger in contrast with the rest of his face and further contributing to the creepiness. It's only somewhat mitigated by the hooded robes he wore from that day forward.
In The Force Awakens, his fanboyish successor Kylo Ren subverts this. The heroine Rey calls Ren a "creature in a mask", likening him to his idol Vader — to which he responds with a Dramatic Unmask that reveals a pretty normal face. Later, Rey slashes him across the face with a lightsaber, but even that scar isn't at all disfiguring.
Strange Nature: Joe and Michelle have some pretty deformed ones, though they looked like that before they came to town. Joe has small lumps and is missing his upper lip, while Michelle has several large lumps on her forehead.
There's also Nikki's puppies, which has a unilateral cleft lip.
Leslie Nielsen's character in Surf Ninjas has half of his face squished by an elephant, forcing him to wear a half-mask a la The Phantom of the Opera.
Suspiria (2018): The viewer is treated a nice and very up-close shot of Olga's jaw being slowly twisted out of its hinges during her iconic 'destruction' scene. Later, we also see Olga's decomposing (but still breathing) body laying on the floor of the mirror room, complete with a few close-ups of her motionless and discolored face, fractured jaw still clearly visible.
In the "Cat from Hell" segment in Tales from the Darkside: The Movie, the cat has killed nearly every member of an old man's family (to get revenge for some brutal animal testing he did to earn his fortune), and the old man hires a hitman to kill the cat. The cat keeps evading all attempts to kill it, getting a few claw swipes at the hitman's face, and then finishing him off by leaping into his mouth, making the hitman choke to death as the cat is crawling down his throat. The old man is taken out when he comes back home, sees the hitman's body, sees the cat crawl back out of the hitman's mouth, and the old man dies of a heart attack.
Terrifier: Art the Clown does this to multiple victims. Notably, this happens to the moves Final Girl Victoria after Art eats her face.
The Terminator, in all of the movies, takes plenty of face damage to show off the cybernetics underneath.
The Texas Chainsaw Massacre (2003): Leatherface has a disease that makes the skin on his face decay. it's only seen briefly in profile, but it isn't pretty.
Julia's Evil Twin Mary suffers from a skin disease that has left her face looking hideously decayed and falling apart at the seams.
In the opening sequence, a younger Mary is shown bashing her sister's face to a bloody pulp as the latter sits in a rocking chair.
The Three Musketeers: One of the guards/torturers in the dungeon is a hulking misfit with a very creepy face, disfigured by many severe burns and dermal neurofibromas.
The climax of Transformers: Revenge of The Fallen has two examples in quick succession: First off, Optimus Prime breaks Megatron's arm and forces him to shoot half his own face off. He then proceeds to go after the Fallen, delivers his famous one-liner, and doesn't wait for the Fallen to give it to him. (Contrary to popular belief, Fallen is actually killed by being punched through the chest and getting his spark ripped out.)
Earlier, Optimus is in a three-on-one fight between Megatron, Starscream and Grindor, and kills the latter by stabbing a pair of hooks into his face and tearing his head apart.
TRON: Legacy: One of the prisoners on the Recognizer has half of his face derezzed. When that particular program looks at Sam Flynn, he just growls.
The Undertaker (1988): When Roscoe kills who he thinks is Ms. Hayes, he presses her face against the stove top, leaving a large red burn mark covering half of it.
The Vindicator: The "accident" that kills Carl has him taking an explosion to the face, and the only skin that remains intact is that around his eyes, and that's only because he was wearing safety goggles — everything else can only be described as "ghoulish".
Wishmaster: The Djinn is particularly fond of mutilating people's faces. In the first film, for instance, he uses his powers to make a criminal unwillingly rip out a cop's lower jaw, tongue still intact.
Wonder Woman features the character Dr. Poison, who covers the lower half of her face with a segmented porcelain mask that makes her look like a broken doll. Towards the end, the mask is torn away to reveal that her nose and mouth are horribly burned and melted, giving her half a Glasgow Grin that's missing half its teeth.
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