An America's Funniest Home Videos episode features a rabbit fighting a snake. The rabbit kicks the snake's proverbial ass, forcing the reptile to retreat up a low-hanging tree, despite the rabbit attempting to yank the snake down for more.
The Boys (2019): In "Glorious Five Year Plan", the Russian facility where Soldier Boy is being held in cryo also contains a hamster infused with Compound V, which makes brutal short work of a guard.
The Adipose in "Partners in Crime". They're adorable little blobs... of human fat. They're usually harmless since they just quietly leave while the taker of a special pill is asleep and leaves them better off as a result. However, if threatened naturally or artificially via a special signal, they undergo Emergency Parthogenesis where they freak out and use everything in the human body they're currently in to make more Adipose. The "Turn Left" timeline had millions of Americans dissolved this way.
The Cybermats in "The Wheel in Space". At least one of their victims actually begs them gently to come closer because he isn't going to hurt them before they do, and hurt him.
On Good Eats episode "It's a Pan! It's a Dish! It's Paella!", Alton is prepping a paella recipe that commonly calls for rabbit meat. But, because of how rabbits are typically viewed in most of the Western world, he has to persuade the audience that rabbits are a viable food option. He does so by referencing the horror film Night of the Lepus before a plush rabbit attacks him, which shows that they're not as cutesy as people think they are. (However, he does still suggest using chicken — especially the thighs — as an alternative, for people who still aren't convinced that rabbits can be food, or who can't eat rabbit meat for religious reasons.)
In an episode of Honey, I Shrunk the Kids called "Honey, the Bunny Bit It", Nick Szalinski revives the school mascot à la Frankenstein, and chaos ensues as it runs amok.
Kamen Rider Drive: Kamen Rider Mach's Signal Danger power allows him to summon a CG creature that looks like a mix between a bullet and a shark; while this might sound scary, it's only about a foot long and has a cute nervous expression on its face. And then it plays the trope straight by growing ten times its normal size and mauling Monsters of the Week.
Life of Riley: When Maddy goes round to an old woman's house to feed her cat while she's in hospital, it suddenly and abruptly turns into a scene from an Alfred Hitchcock movie. Eventually, all she can do to get out of there in one piece is to open a can of cat food and shove it through the letter box, almost losing a finger in the process. You can imagine her reaction when she was then asked to go back and change the litter tray.
Lucifer (2016) mentions Azrael, the Angel of Death. She actually lives up to the title, abilities-wise, but when she shows up for an episode, she's essentially an adorkable young girl with glasses and a bob haircut who looks like she's late for chess club. She's also really clingy and needy and wants to hang out with people, rather than the disassociated being you'd expect from a reaper of souls.
The Mandalorian: Jawas are half the size of a human, dressed in cheap robes, and armed mostly with sharp pieces of scrap. In most Star Wars media, they are portrayed as nothing but pests. They are still pests in this series, but dangerous ones. The Mandalorian discovers them stripping his ship for parts, and while he kills quite a few, their sandcrawler is completely impervious to his weapons, and their sheer numbers are able to overwhelm him. In the end, after a humiliating defeat, he's forced to negotiate in order to get his parts back.
The Child is an infant of the same species as Yoda, able to charm young children and hardened mercenaries alike and use the Force to heal mortal wounds. He can also use those same powers to suspend a charging beast in mid-air or crush the throat of anyone he thinks is threatening his guardian.
The title creature in "Bunny Therapy", a fourth season episode of The Middle, eventually takes over one of the Heck's bathrooms.
Misfits: A smackhead with a power to materialize his hallucinations does acid while switching through shows about rabbits, golf and assassins. He ends up conjuring a rabbit-headed assassin with a golf club.
The Furbie-esque Nubbins in Sanctuary are a variant of this — they're only dangerous in large groups and when being directly attacked, but their extremely high reproductive rate and lack of predators outside their natural environment make them potentially highly destructive to the ecosystem. Unfortunately, they're a Hive Mind far brighter than they seem, and are more than willing to sacrifice individual lives to escape and spread. Look what happens to the large, vicious wolf-like abnormal the team sends after the nubbins. Look at the bones, indeed.
An episode of Sliders has an Earth with literal (and giant) carnivorous rabbits. They stay there very briefly.
Star Trek: Lower Decks: Season 4, Episode 2 features a creature zoo which includes the Moopsy, a rolly polly doe eyed creature that speaks its name. Unfortunately, it's a bottomless pit lined with fangs that it uses to literally drink the bones of its prey.
A bunnicorn looks like a cute bunny rabbit with a small horn on its forehead like a unicorn, but it carries venom sacs. Anyone who ingests its toxin will vomit black bile and die.
One of the top-secret projects at Daystrom Station is a tribble (an otherwise inoffensive furball) that's been modified into an attack creature.
Lunatyx from Ultraman Ace, a rabbit-based choju hailing from the moon. As it turns out, the moon used to be populated by a race of Human Aliens... until Lunatyx attacks and turns it into the barrel wasteland everyone is familiar with.
King Molerat from Ultraman Tiga, a behemoth-sized hybrid between a hare and a guinea pig, whose huge, fluffy ears are it's most prominent features. Although it's a benevolent example, preferring to spend it's days sleeping instead of going on a rampage, and is one of the few monsters spared by Tiga during the show.
In one episode of Xena: Warrior Princess, sidekick Gabrielle must fend off a vicious attack by what is essentially the Rabbit of Caerbannog.
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