As a Moments subpage, all spoilers are unmarked as per policy. You Have Been Warned.
Even though a lot of moments in the series are generally Played for Laughs and end up being Nightmare Retardant in general, there are still many moments that are terrifying, even for the standards of the series.
- Sonic's "adventure" with Toejam and Earl. The beginning of the episode makes it look like he's having a blast with the two aliens as he helps them capture humans. Then as it seems that he's about to have it all (the job seemingly paid a lot of USD), Tails wakes him up and it's revealed that Sonic had an acid trip four days ago and just wandered off. "Toejam and Earl" were actually a garbage bag and a dented chair, and that Sonic actually ended up throwing jars at humans, injuring a lot of them (with pools of blood and groaning as an extra bonus). Cue Sonic and Tails leaving and evading the cops.
- Sonic and Co. even recreate this episode during Season 6 to attempt to stabilize the time loop. Thankfully it ends up being a bit funnier, but added bonus points for Earthworm Jim (as a Yoshi) rocking in a fetal position.
- Soniqua. She is a mutant brain hybrid that was quickly made after a drunken one-night stand between Sonic and Mother Brain. She is a hideous looking monster that has Mother Brain's "body", Sonic's hair, and a deformed face. So far, she seems to be incapable of dying. She can eat bombs, get dunked in lava, and even be thrown out into space - she'll always come back with no signs of pain.
- Soniqua will also KILL anything that even remotely threatens Sonic. When Soniqua sensed that Mario killed her father in Season 6, she started by killing Mario's mafia one-by-one, starting with Bowser. She even mailed his head over to his office to let him know that she's coming for him.
- Soniqua will even prioritize Sonic's protection over Mother Brain's protection. During Season 5, when Sonic and Tails are tasked with killing Mother Brain, the giant brain monster orders a bunch of Metroids to kill the two. Soniqua ends up turning into a giant monster and destroys Mother Brain's lair in the process, upsetting her mother.
- Mike Tyson dies twice to Soniqua, and both deaths are pretty graphic. The first time was during the battle against Mario's mafia in Season 2, and Soniqua grabs him with her tentacles and splits him in half. The second time is more brutal, and he's shown resting in a locker room. Out of nowhere, Soniqua strangles him with her tentacles and gives enough pressure that his head is ripped off from his body.
- When Soniqua finds out that Mario killed Sonic, she swears to kill all of his goons (in a Shout-Out to Kill Bill). Her first victim: Bowser. He is Killed Offscreen, but Mario receives a package from Soniqua, it's Bowser's severed head covered in blood with a note that says "Me going to kill you".
- Kirby. Oh boy. He's not the cute friendly puffball that he is from his original series. He's a sociopath who enjoys killing harmless creatures for fun and in his first appearance, even disgusts Sonic with his actions. He even coerces Sonic into killing them too. It's just a good thing that he's generally leaning towards Sonic's side as opposed to someone like Mario's.
- During the battle against Mario's mafia in Season 2, Kirby somehow beats Mecha Hitler up by hitting him with an umbrella repeatedly. And his death is pretty gory.
- During Season 4, he becomes a Hollywood director, and every time his Waddle Dee servants offer him anything, he bludgeons them to death with an umbrella, with the deaths being pretty gory and detailed. Pay attention to when he eats one of the Waddle Dees during his impulse murdering - he sticks his finger in his throat and vomits. Considering he's trying to keep a skinny figure, it's strongly implied that he's bulimic, something that a lot of Hollywood actors and other people trying to maintain a presentable appearance would do in real life.
- After being Demoted to Extra after Season 4 (Fox and Falco made a mention about him in Season 5 and he appears as morbidly obese in Season 6, threatening to kill Sonic and Co for ignoring him), he plays a role in Season 7 in Kung Fu. He attempts to be a pacifist, but once Sonic goads him to kill some asshole karate people, Kirby figures he could just do a little murdering for old times sake and stop murdering for good. Cue an absolute blood bath, and then we have what's shown on the page image above. Kirby loves his brief return to murder so much that he decides to go back to Dream Land and murder some more.
Kirby: "OH MAN I FEEL GREAT! I forgot how much I love to murder! I LOVE IT! I'm gonna go back home and do it some more. Thanks Sonic. Murder murder murder murder murder."- During the "Where Are They Now?" Epilogue, we get a shot of Kirby holding a skull of a Poppy Bros Jr on top of a broken Whispy Woods with a couple of mini-bosses severed. Among these mini-bosses are a Phan-Phan with its eyes pulled out and a Cook Kawasaki cut in half - both in gory detail. He's even described as the "Le Bron James of Hitler". It's just fortunate that the events of the epilogue were retconned at Season 8.
- Mario. Unlike the happy-go-lucky mascot of Nintendo, he's the head of a mafia organization. He has a ton of connections with villains and drug cartels and will usually hire hitmen to kill anything that gets in his way or even try to overshadow him.
- Sonic happens to meet him when Tails borrows money from him to help get him out of jail, and Mario immediately tries to coerce Sonic into doing work by threatening to murder Tails (which doesn't work because Sonic wouldn't really care if Tails died). When Sonic messes up with the Double Dragon, Mario outright tells him that he would've had him dead there. But when Luigi dies the following episode from an acid trip, Mario finds out and wants Sonic dead. Considering Mario is Made of Iron here, he survives a fall in Donkey Kong Country, recruits a lot of his villain ties and even finds people who crossed paths with Sonic to add to his mafia crew, and we have a huge crew of people who want the hedgehog dead. Yeah, you don't fuck with Mario.
- Why did Mario want the Angry Birds dead? Because they were getting too popular (also doubles as a Take That! to the franchise at the time). Even their deaths were pretty brutal despite being obnoxious jerkasses, as Sonic reveals he gave them gum laced with alka-seltzer and rice, which makes their mouths foam and their stomachs explode from the inside.
Sonic: "Oh I'm glad you like it! it's my own recipe, mostly Alka-Seltzer and rice. Enjoy it, it's gonna explode your stomachs."- When Mario sends Sonic, Tails and a dead Luigi to Donkey Kong Country, he asks them to get some TNT Barrels because he feels like "blowing up some worlds". Considering that a Koopa Troopa that owned a gas station in Season 4 is grateful for Sonic because "he killed the genocidal plumber", this implies that Mario ruled certain areas with an iron fist and if anything didn't go his way, he'd just blow them up without any second thought.
- When Mario gets revived by Princess Potato in Season 6 due to time travel, his first order of business is to hire anyone to kill Sonic. His first crew is Ghost Rider, Boba Fett, and Dog the Bounty Hunter. They arrive at Sonic's mansion and ask the hedgehog if he's Sonic. When Sonic tricks them into attacking Eggman, they put him into a hold that thankfully Earthworm Jim takes out. When the Avengers are successful at kidnapping Sonic later, Mario just outright shoots him right then and there.
- Murdering Sonic brought upon world peace, but being Mario, he ends up taking over the world instead. Cue Mario bringing back his dead crime pals and then taking over the world, starting from Dream Land. Later at the end of the episode, lots of areas have been littered with crime since the takeover.
- The Duck Hunt episode is full of these.
- The stress of running a mafia business has hit Sonic hard, and has lead him to being very delusional. He blindly shoots at a lot of people, even threatening to shoot Tails.
- Sonic mistakes the Duck Hunt dog for a "radioactive moose" as well. Whatever's happening to Sonic, it's definitely set him to a downward spiral.
- Said dog beats the living shit out of Sonic after his signature laugh drives Sonic insane. And the dog beats Sonic to a pulp too. The only reason why Tails refuses to do anything about it is because he's not shooting a dog.
- It's outright implied that the Pokemon Trainer used Soniqua to kill many trainers who refused to pay their end of the bargain. Considering that the Duck Hunt Dog here was powerful enough to survive a dragon unscathed, there's a chance that said dog dealt some hard damage on other Pokemon as well (considering the dog was fighting a Pikachu during "It's On"). We also got to see what the dog does to Thunderhead, and it's pretty bloody. Thankfully alleviated when the dog ends up humping Thunderhead later.
- Even though El Padrino himself ends up being more funny than terrifying, his "Marmosets" are revealed to not be "cute little monkeys", but his cocaine-addicted cannibalistic pop group. He points out that he needs to come up with better names for them. When they come out, their eyes are black with red pupils and they look like they're zombified. One of them even tries to eat Earthworm Jim.El Padrino: "Actually Marmosets are also the name of my female pop group that I keep around for entertainment. I should probably come up with some other names. Anyway, they're coked out of their minds. They haven't eaten in years. So you three (Sonic, Earthworm Jim, and Eggman) are going to make a perfect meal for them."
- Season 4's finale involves Sonic blowing up the movie theater full of people inside of it. We even get to hear panicked sounds of screaming before the theater explodes and seemingly kills everyone, including all of Sonic's friends and others that were invited just to spite Tails. Thankfully becomes Nightmare Retardant when Eggman, Earthworm Jim, and Soniqua all were revealed to be alive and that they knew there was something up and Sonic took quite a while before the theater blew up, giving them all time to evacuate.
- Earthworm Jim does not do well in deserts, and hanging out in Tatooine dehydrates him to tremendous extremes. Luke and the Sarlacc both want to die, but Sonic keeps extending the conversation. Having enough, Jim throws both Luke and his spaceship into the Sarlacc and shoots the giant worm (who explodes in blood).Jim: "GET ME SOME FUCKING WATER!!!"
- Sonic tortures Crash Bandicoot so he can get his Epoch back by putting him on an electric chair. This is done in a similar manner to the original scene that it imitated
from the first Taken film, but it Crosses the Line Twice when Sonic asks Crash how he did with the imitating the scene while the bandicoot still getting his insides fried as he is screaming for his life. - Season 7's driving point is the "Creator" messing with Sonic. It gets especially creepy in "Kung-Fu" when Sonic chooses to have sex with one of the characters, then she turns into random other unsettling characters before turning into Mother Brain, to Sonic's disgust.
- Sonic Mania has some incredible Nightmare Fuel that isn't Played for Laughs like many other episodes. Sonic returns after realizing that there's a new Sonic game that they hired replacements for.
- After New Tails talks about Sonic Mania being "subtle", Sonic shoots New Tails in face face without any word. Small animals immediately feast upon Tails's corpse.
- Later, when New Sonic suggests sharing the spotlight, Sonic ties him on a loop with some of the animals coming in to eat him alive. We get to see it and it looks fully graphic as well.
- When Sonic announces that he's taking over the game, the critters end up destroying the rest of the game. In the following episode, the sky and water are already red and a bunch of Eggman's other robots are getting eaten by the critters. Keep in mind these are robots, not organic.
