Every now and then the hero runs across a big animal he would rather not disturb. It's a bear, or a tiger, or Cerberus.
Correct procedure is to back away slowly, making placatory sounds such as 'Niiiice kitty... good kitty..." then run just before the pounce.
Occasionally the Kitty turns out to be an actual Nice Kitty, and acts like a giant kitten.
- Complete inversion on Azumanga Daioh: The animal is tiny, not big; the character approaches it while placating it instead of backing away, and instead of it turning out to be nice, it turned out to be exactly as dangerous as it didn't look.
- Robin (Tim Drake) once found himself stuck in a pit in the Armstrong's basement with an old circus lion "The General" had stolen. As he backed away and murmured placating things to the lion and it prepared to pounce he recalled that the lion's trainer was originally from Germany and snapped off a command in German it actually obeyed giving him enough time to get out.
- Disney's Aladdin. Aladdin says to Rajah, "Down kitty...Look! A mouse!...Scat...C'mon, good tiger... Take off and go!...Down kitty". Infamously, many people misheard it as "Good teenager, take off your clothes," which led to it being edited out of later releases.
- Mike in the Teaser Trailer for Monsters, Inc.: "Nice doggy. Nice big doggy."
- The Aristocats: "Nice doggy, nice doggy, roll over, play dead!"
- Donkey in Shrek when he's cornered by Dragon. "My, what big, sharp teeth you've got!... I mean, what white, sparkling teeth you've got, and do I detect a hint of minty freshness?" She ends up falling in love with him, which gives him a whole different set of problems.
- In Coco, Ernesto tries in vain to sooth angry Pepita as the latter approaches him on stage for a final asskicking.
- You think Tim Allen's character is going to do this when he sees a dog in his first foray as Santa in The Santa Clause, but he subverts it: "Nice... teeth!"
- In Octopussy, James Bond commands a tiger to "Sit!" (in Barbara Woodhouse's distinctive tone). And it does.
- In Ghostbusters (1984) when Louis Tully is confronted by the monstrous Vinz Clortho, he tries to soothe it with, "Good doggie...nice little pooch..."
- The titular lion in Secondhand Lions. Definitely a very nice kitty, she is impossibly tame, though very protective of her cub (Walter).
- Pee-wee's Big Adventure - stranded in the middle of nowhere in pitch dark, Pee-Wee hears nearby growling and nervously goes "nice kitty..." When he turns on a light, he finds himself surrounded by big predatory animals that absolutely don't belong in the American desert southwest.
- In Black Hawk Down, Twombly feels the need to address a donkey trotting down the street near him:
Twombly: Nice donkey.
- In Batman Returns, Catwoman and the Penguin use this on each others' pets (a canary for the Penguin and a black cat for Catwoman). It's an ironic example in that both are the aggressor rather than the victim, the two animals being completely harmless to humans.
- In Chaplin's The Circus, the Tramp ends up locked in a cage with a lion. Fortunately, the big cat is too lazy to go after him.
- Crow has a habit of saying "Kitties!" whenever lions or tigers are shown. A fan even writes asking Crow to say "Kitties!" a few times.
- There's an old saying that goes: "Diplomacy is the art of saying 'nice doggie' until you can find a rock."
- Our Miss Brooks: Happens with "Peanuts, the Great Dane" in the episode of the same name.
- In a King's Quest V death, Graham says "nice birdie" to a roc hatchling about to eat him. Of course, that death is averted if he gave the remaining meat to an eagle and grabbed the pendant on the roc's nest before the egg hatched.
- Fallout 4: "Uh, good Deathclaw. Good boy. Stay." 
- Cornered Sentry from Hearthstone: Heroes of Warcraft summons 3 1/1 raptors for the enemy when played. Her summoning quote?
Cornered Sentry: Nice little raptors...*
- A subversion in The Flintstones: Barney sees a Bantydactyl and cheerfully says "Here, pussy pussy" to it until it cheerfully opens its mouth and grabs him leaving only his feet exposed.
- Avatar: The Last Airbender: Aang flees a big horned gorilla thing until he realizes it's King Bumi's pet. Then he tentatively asks, "...Flopsy?" To which Flopsy responds by grabbing him and cuddling him.
- An episode of SpongeBob SquarePants shows Patrick trying to do this with a lionfish...while trying to lure him away with sausage. But he eats the sausage, so this fails.
- The Simpsons: Homer is terrified of some grizzly bears he and Bart run into while on a camping trip, and murmurs "Nice grizzlies...Nice grizzlies..." Bart, meanwhile, is completely unafraid ("Later, grizzly-dudes").
Homer: "Why, hello little birdie- AAAAAHHH! COVER YOUR EYES!!!"
- After Homer and Ned get kicked out of Las Vegas, they decide to walk(!) back to Springfield. They are quickly set upon by a pair of vultures.
- Donald Duck does this after he roughhouses a mountain lion, who he initially thought was his nephews in disguise.