As a subtrope of Amusing Injuries expect this to be played solely for laughs.
However, the cause of this doesn't always necessarily have to be physical violence. Sometimes a character can have their face sinking by itself as a reaction to some unpleasant sensation, mostly horrid smell or eating some really bad food.
Contrast Cranial Eruption, where injuries cause bumps instead of dents.
- Pokémon: The Series: During "Journeys", Goh sometimes gets the Pokéballs he throws at the Pokémon deflected right back at him, caving in his face.
- In the eighth chaper of School Zone Girls during PE class Yokoe gets hit in her face by a basket ball. The next panel is Yokoe downed on the floor with her face sunk in like a rubber balloon while her friend Yatsude comments that now Yokoe's face looks like a sea urchin.
- Dick Tracy: This happened at least once to the villain Putty Puss, whose gimmick was that he could rearrange his facial features to impersonate other people. After figuring out that a celebrity was actually Putty Puss in disguise, Tracy revealed the deception by socking him in the face, which crumpled around his fist.
- One single-panel cartoon in Playboy has a bar patron with an imploded face. The bartender smarmily asks, "Martini dry enough for you, sir?"
- Frozen: A blink-and-you'll-miss it moment, but Prince Han's face is briefly caved in when Anna punches him.
- Hercules: Upon emerging from the River Styx carrying Meg's soul and with his godhood restored, the first thing Hercules does is give his Evil Uncle Hades an Offhand Backhand, which caves his face inwards. Being a god, Hades shrugs this off shortly afterwards.
- The Muppet Show: This happens to Statler a few times in the series. His "punched" face has no visible nose.
- Played with in "Scoobynatural", an episode of Supernatural where Sam and Dean cross over into a Scooby episode. When they first arrive, cartoon Dean slaps cartoon Sam in the face, briefly leaving his handprint on Sam's cheek. Sam has to rapidly shake his head back and forth to make his face return to normal.
- Not in the games itself, but in one of the behind-the-scenes concept art of Metal Slug X shows a rebel soldier's entire face sunken in after being hit by a bullet, rather than the more realistic Boom, Headshot! . The picture can be seen in the game's gallery after beating the final level, or on Twitter.
- Kill Six Billion Demons: Allison reacts to a surprise encounter with the villainous God-Emperor Gog-Agog with a Super Strength punch to the face. Being The Worm That Walks, Gog-Agog is unharmed by having her head turned inside out, but is a bit annoyed to be the butt of yet another Amusing Injury.
Gog-Agog: owie zowie! nobody gives me a fair shake!! [pops her nose back out]
- When the Grrl Power villain Hench Wench punches mister Amorphous (a hero with stretching abilities) in the back of the head, we get a face sunk outwards. Which is deeply traumatizing for everyone involved, not the least of which being his girlfriend.
Mr. Amorphous: Wow, that felt weird. Kind of like when your eyelid gets flipped over, but for my whole head... What?
Heatwave: Oooooh, baby. I'm gonna need some time to process that.
- Scandinavia and the World: In Potato shaped like a potato, this is Denmark's reaction to eating raspeballer, an extremely salty Norwegian potato dish.
- Sequential Art: Scarlet tries to free the goat-man Thumbless from the Winter Witch's clutches by dousing her with water, à la Dorothy versus the Wicked Witch. Scarlet throws a bucket with a champagne bottle at the Winter Witch, not noticing that the water in the bucket is frozen solid. The Witch takes a solid ice block to the face in strip #921, and the resulting imploded face is seen clearly in strip #924.
- Celebrity Deathmatch: During the Jim Carrey/Mariah Carey fight, Mariah punches Jim hard enough to turn his face into a crater. Jim plays it off by asking if Mariah saw the "tiny fly" that "landed gently" on his face, before stretching it back to normal.
- On Chowder, the titular protagonist eats a whole puckerberry before Mung Daal can warn him not to. It is so sour it causes Chowder's entire head to pucker in on itself, leading him on a journey inside his own body.
- In The Fairly OddParents episode "A Mile in My Shoes", Timmy gets a dodgeball straight into his face. When the ball falls off, his face is concave until Wanda fixes it. It happens again later in the episode when he falls face-first into a pit filled with dodgeballs.
- Looney Tunes: In "Porky Pig's Feat", Daffy accuses a hotel manager of insulting him and gets way too far in his face about it.
Daffy: Hey, look! A Dick Tracy character: Pruneface!
- On the Roger Rabbit Short "Tummy Trouble", Mrs. Herman points her finger at Roger as she warns him not to let Baby Herman get hurt, pushing it so far into his face it caves in briefly before popping back out.
- SpongeBob SquarePants: In "Ghost Host", SpongeBob pounds on Squidward's door and accidentally pounds his face in when he opens it.
- Tom and Jerry: In Cue Ball Cat, this happens to Tom when Jerry throws a billiard ball at his face.
- One of Bill Plympton's favorite things to draw. As early as his short 25 Ways to Quit Smoking he was using this gag; one of the ways suggested involves punching yourself in the face every time you take a drag.