Values Dissonance heavily ties in with the frequency of the trope in anime, due to Japan's very different idea of what's okay for children.
Attack on Titan has this covered with the fact that their human prey is Eaten Alive. Titans themselves seem to have a wide variety of preferences for exactly how they eat humans; some are stuffed whole into mouths and crunched up, some are bitten in half, some are slurped down, some are dropped straight into the gaping mouth, one was even halfway down feet first being slowly gnawed down.
Eren and Mikasa's mother stands out; the Titan actually bent her in half to stop her struggling before placing her in its mouth and snapping down everything but her feet.
The Female Titan loves this trope, finding innovating ways to crush and kill humans, sometimes using them as a yo-yo's and soccer balls. The anime toned the violence down heavily, but it's still there as Freeze-Frame Bonus.
Kaien Shiba's death is pretty horrible. Firstly, he has his body taken over by a Hollow, going on a rampage until he is killed by being impaled on Rukia's sword. Then the Hollow's body who he's fused with gets transported back to Hueco Mundo, and forms a new spirit body in the form of Kaien. Adding to this, said Hollow is soon eaten by Aaroniero Arruruerie, who later appears to Rukia as Kaien, and engages her in combat. Finally, Aaroniero's imitation of Kaien is stabbed by Rukia again - this time through the face. Considering the fact that Kaien's body was being used as a puppet for quite a while after his death, it just adds to the nastiness.
What happens to a Bount when its Doll is destroyed is not pretty.
Chirinno Suzu has Chirin's mother being strangled to death by the Wolf King, Chirin accidentally knocking over a bird's nest full of eggs after the mother has been killed by a snake, and finally, the Wolf King being stabbed to death by a now-adult Chirin, who has transformed into a demonic ram.
In Digimon Adventure 02, the still Not Quite DeadBig Bad, now possessing Oikawa, a lonely and obsessed man, ends up dragging the protagonists to a surreal dream dimension. There his spirit exits Oikawa's body through his mouth in an extremely violent and painful-looking manner. (Slow down the tape and the blob of energy that springs from Oikawa's mouth has a grinning face). Once he regains his body, he turns on the two servants he had created using Oikawa and proceeds to torture them and kill them in an unspeakably gruesome way, which traumatises the Digidestined for quite a while as they fear their partners will be subjected to the same fate.
Also, in Digimon Tamers, Beelzemon kills Leomon by STABBING HIM THROUGH THE STOMACH, with his bare claws. There's no blood, but they do show that Beelzemon's hand has gone all the way through Leomon's body and is now poking out of his back.
One Heel-Face Turn later, and Beelzemon comes this close to having one of these. Specifically, via the D-Reaper shooting what were essentially flying knives into his spine, from the back of his neck down to his tail. The scream he lets out as it happens is pretty much the icing on the cake, and the cherry on top is that his own partners (two toddlers), witness it live on TV. Sweet dreams, kiddies...
Digimon Adventure has this is spades in the Dark Masters arc. The first two Dark Masters get frozen by an ice blast at point blank range and drilled from the nose to tail. Whamon gets impaled through the head. Earlier Myotismon gets kicked in the crotch by a huge ball. Metal Etemon gets his chest cracked by a huge hammer, and then he gets impaled.
Dragon Ball Z is full of them. Many are censored so that parts of them (but usually not the death itself) are not seen in the edited version. Aside from the bloody ones, there is a moment partially edited out of the edited version (but still making clear the character is dead) where Super Buu turns to liquid and goes down a deranged gunman's throat, making him expand and explode. It is also gruesome to watch the first time Cell absorbs someone - he jabs a rich man with his tail and sucks him in one bit at a time, causing him indescribable pain as he shrivels up before he is completely sucked into Cell's tail.
There's a scene in the original manga during the Cell arc, where Gohan in SSJ 2 transformation, goes in a rampage killing brutally all the Cell Jrs. around. Meanwhile the anime only shows the Cell Jrs. exploding into gas, the manga goes as far as showing Gohan ripping apart their arms and breaking them in half.
Frieza's death at the hands of Trunks. Cut down the middle, sliced into pieces, then blasted into atoms. Overkill much?
Even before then, Frieza's near-death on Namek was very graphic. In the manga, though, it was even worse in terms of gore.
Krillin exploding in the Frieza Saga being a particularly traumatic experience for Little Timmy, who was watching with tears welling in his eyes. Then again, many other characters had been killed by that point on Namek, not to mention the Saiyan Saga so it's quite likely Little Timmy was in therapy at this point.
Yamucha's death by the Saibamen during the fight with Nappa and Vegeta deserves a mention. Krillin runs to his body and listens for a heartbeat. After screaming, "He's dead!" he then burst into tears. The death was also captured by the news crews, so everyone at Master Roshi's house witnessed the death. There's even an extended period where the visual keeps alternating between Bulma's stunned face and the scene on the television of Krillin crying beside his body.
Did not happen in the original dub (you know, the one that spawned the Over 9,000 meme). In the original dub, Yamcha is simply vaporized by the Saibaman's selfdestruct.
How about Chi-Chi's death? She slapsMajinBoo after he killed her oldest son...so he turns her into an egg and crushes her beneath his foot. In front of her other son (who is approximately eight).
A special mention should probably go to Gold Eye of the manga-only wolf arc: his chest explodes as result of Hyouma's Metsu Hen'i Battouga. You can see bits of guts around the bloody cavity. And he doesn't even die straight away, managing to slip in a few final words before finally drifting off permanently.
If you wonder why some don't think the censorship in Voltron is so bad, look at every other death in Go Lion. Kids were evidently used to this in Japan, but American kids in the early 1980s, no way. It would give them nightmares.
Right from the very first episode, you have nuclear holocaust wiping out the Earth, and graphic depictions of slaves being squished to death in the arena for sport.
And you have Takashi Shirogane's untimely death in one of the early episodes- this being one of the principle members of the team. His brother Shou suffers the same fate, albeit taking surviving Big Bad Prince Sincline with him. Voltron (which pretended both characters were the same guy, Sven) made a shoddy job of covering both of these up, given some of the other characters are visibly in tears on both occasions.
Other characters, main and supporting are shown getting brutally massacred, murdered, committing suicide or being otherwise dispatched.
Hokuto No Ken has scores of this in literallyeveryepisode and chapter, but a particularly hard-to-watch example is when Kenshiro is fighting a serial killer and strikes his meimon acupressure point, causing his back muscles to involuntarily contract far beyond their normal point. After Kenshiro leaves the helpless, screaming and sobbing man for dead, an on-screen timer counts down; when it reaches zero, the murderer's spine breaks backwards and he dies in an unnatural, contorted position.
The Chimera Ant arc of the Hunter × Hunter manga, with the titular Chimera Ants chopping up people while they're still alive and feeding them to their queen. Also, one of them cutting open a character's skull and manipulating his brain with needles to get information about the manga's Functional Magic out of him.
In Osamu Tezuka'sKimba the White Lion, the death of Kimba's parents are pretty heartbreaking for many adults. Kimba's father gets shot, and his mother drowns while trapped in a boat just a few months later.
Their deaths are tame compared to the eponymous character's death in the original manga and movie. Kimba performs a Heroic Sacrifice for his human friends, who needed food and shelter while lost in a blizzard, by jumping off a mountain to impale himself with a kris sword so they can eat him.
There is a Buddhist fable about a rabbit that kills itself by jumping into a fire so that a starving holy man can eat it. A rendition of this story is included in Tezuka's later manga series Buddha (which in general is not a kids' story), over twenty years after the first publication of Kimba.
While hardly the only example in Kinnikuman, Ramenman kills Brockenman in the anime by turning him into noodles and eating him, which is a lot more disturbing than it should be. In the manga he rips Brockenman in half with his Camel Clutch. Messily.
Macross Plus Movie Edition. Guld Goa Bowman's death scene. He rams an enemy AI fighter with his own plane, not before having to accelerate so hard that his fists over his stomach breaks his ribcage (and mashes his guts), his eyeballs are squished by their own weight, and he vomits blood all over his helmet.
Of course, Macross Zero has its own moments in a shot of DD Ivanov's face melting off when power beams destroy his fighter and when a red shirt fighter pilot gets hit in the cockpit and literally explodes, covering whatever remains of his canopy with gore.
Nora got blown out of her cockpit and then hit by a anti-air beam.
Presumably the reason why Episodes 27 and 35 of Monster Rancher were skipped after their first airing by the Fox channel. In the former, Gray Wolf is stabbed in the throat by Tiger with his horn (though the cause of death seems to be the destruction of his baddie crest from said stab). Especially considering that Gray Wolf is Tiger's brother who was turned evil by Moo. In the latter, Naga commits suicide by falling over the edge of his castle, despite the others trying tosave him.
Undine commits suicide in Episode 24, jumping into the fire after Golem tries to save her despite her betrayal.
Mother Keeper, first one being when we first meet Turkes and he murders a little girl and then beheads her brother. Later on, during Syal's backstory, Allen gets the top of his head blasted off. Then in the final part of Hunter, Silas suffers a similar fate.
Naruto has loads. The first arc gives us Kakashi (seemingly) being sliced to bits with spiked chains, and Zabuza dies an amazingly Rasputinian Death. The second arc has the random Rain ninjas that Gaara gets with his sand attack- they explode so hard that Gaara uses an umbrella to avoid the blood.
One Piece: *sob* Portgas D. Ace. That's what being punched with a fist of lava and having your insides melt down as a result will do to you.
The same token, Whitebeard's Robocop-esque death. (Given the ethical arguments being made in that scene, this is probably designed to prove his moral correctness by reference to Benkei'sstanding death.)
Also the victims of Magellan'sHydra poison are coaxed in a glob of extremely painful poison that will eventually melt them. Uuuuuk...
Lucario in Pokémon: Lucario and the Mystery of Mew. Sure there's no blood, but we're treated to the poor guy sobbing and spasming in excruciating pain while he slowly disintegrates, and it's about six steps more horrifying than the series full of cutesy monsters tends to run.
Even more so considering he's one of the good guys, and it's usually a Big Bad who gets this type of death.
Lucario is far from the only movie character to get this treatment. Celebi had the life force drained from it until it became a withered, dessicated husk. Latios graphically drowns to death in a Heroic Sacrifice. Darkrai, similar to Lucario, is graphically disintegrated. Zoroark is graphically electrocuted to death by the Big Bad while her young son is Forced to Watch. The last one is notable for easily being the most graphic, brutal death of the entire series.
Not to mention Ash getting turned to stone later in that movie. Granted he got better.
Hiroko Asahina's death in RahXephon is utterly horrifying, especially when the rest of the show's violence is rather tame. Ayato goes out to fight the Monster of the Week without realizing that it's been linked to his Unlucky Childhood Friend. He rips it apart like he would any other monster, only realizing what he's done when it spells out Asahina's last words. He comes home to find that all the damage he did was mirrored on her, and he just ripped his friend to pieces.
Some of the villains die in rather unpleasant manners, placing emphasis on the fact that these deaths are at the hands the heroes. There are two instances where we see the flesh melt off of the bones of the heroes themselves.
the three cats get torn apart by one of Galaxia's minions in the final arc. Like everyone else who died that arc, they got better, but its still pretty unsettling.
Sailor Venus' death in The Ninetiesanime is particularly violent (spikes impaling her in the stomach, then being imploded with fire). Don't worry, she gets better.
The anime also has Neflite, who gets stabbed by a mook with a thorn. Unlike when Ann, Diamond, and even two nonfatal instances of Tuxedo Mask get stabbed, the stabbing is fully shown onscreen, the thorn remains embedded in him despite Molly's attempts to remove it, and there is green blood everywhere.
Doctor Tomoe's possessor Germatoid in Sailor Moon S gets stabbed in the eye. Although there's no blood this time, and the violence is downplayed by Germatoid's final word being "Owie!"
Heck, all of the deaths in S season were disturbing, but the three that stood out the most were Telulu's (being blown up by her own Hyper Telulun), Viluy's (being disintegrated alive by her own nanobots, albeit bloodlessly), and Eudial's (dies in a car crash, which is more disturbing due to its mundane nature).
Viluy's death has the rare distinction of being scary in both the original Japanese and the Cloverway dub.
In an episode of Speed Racer, one of the other drivers gets stuck in a mass of molten pitch. As he climbs onto the top of his car to salvage his stolen loot, a column of lava strikes his face, and he falls and sinks into the pitch. Crashing and dying is commonplace in the show. Racing is Serious Business.
There was also the fate of the crew of the laser tank: Molten lava poured into the tank through a breach made by an ejected rock.
An entire research team is boiled alive four and half minutes into Steamboy.
In Toriko's Puffer Whale arc, Toriko, Coco and Komatsu come across a pit of toxic insects. Then an unlucky Bishokoya falls in, gets swarmed while screaming in agony, and is reduced to several bones on the floor. OUCH. Later on, several animals are sucked dry by killer trees, The two Wall Penguins in Ice Hell are killed when Tommyrod sends a giant parasite to burrow through them in a VERY gruesome manner, and finally, Tommyrod himself has his "Child", a gigantic insect abomination explode out of his body, leaving him an empty husk (It's implied that he got better, but still.....)
The Karmic Death of Thrust. During his monologue, his foot get caught in the transforming Unicron's gears. By the time he notices it's up to his thigh, and he gets slowly sucked in and crushed while he begs Galvatron for mercy. The final shot is of his head swelling from the pressure and then Unicron's armor finally closing over him with a jolt of electricity. This is a kid's show?
Starscream's death toward the finale was, aside from being pretty sad, also pretty horrifying. While he's getting graphically disintegrated by Unicron's attack, you can clearly see his arm fall off before his body is completely destroyed.
Shoukei is almost given this in The Twelve Kingdoms, when the peasants sentence her to be dismembered. She's saved in the nick of time, though.