The contents will not always be water — it could be jelly, ink, or something more... foul. Either that or some jerk will bring out the hose.
Expect college science geeks and/or medical students with too much time on their hands to build a water balloon slingshot out of lab materials, or some other ridiculous contraption. They might also fill their water guns with liquid chemicals.
Wet T-shirts and swim suits may lead to Sexy Soaked Shirt.
Compare Bubble Gun.
- There's a rather amusing American commercial for hydrogen-cell cars that asks the question "What if we could replace something harmful with water?" Cue Matrix-style gunfight with water guns in place of real guns and water balloons in place of grenades.
- Cowboy Bebop: Ed uses water guns filled with "stinky gas" in "Mushroom Samba".
- The Melancholy Of Haruhi Suzumiya: Haruhi subconsciously modified model guns into firing pressurized water balls with unimaginably explosive firepower. Dual squirt guns turned dual mini water-grenade launchers/pistols.
- Yotsuba&!: Yotsuba, Jumbo, and Yanda held a water balloon fight inside the house. When Yotsuba was supposed to be housesitting no less. And she even started it by ambushing Yanda with her water pistol.
- Regular feature on Calvin and Hobbes. An Escalating War usually follows, with the local weapons-of-mass-destruction equivalent being the garden hose, or on one occasion a filled kiddy pool. In the Print Bonus story of The Lazy Sunday Book, Spaceman Spiff's Zorcher and Demise-O Bomb are in Calvin's reality a water pistol and water balloon, and only succeed in making their respective targets, Susie and Calvin's mom, wet and angry, though the grounded Calvin is still plotting a new watery prank in the last panel: a Bucket Booby-Trap.
- Appears in some Garfield strips.
- At least once in FoxTrot, Jason and Marcus were firing squirt guns filled with fruit punch. When they stopped to refill, they were swarmed by flies.
- In Black Crayons, they serve as the ideal weapons whenever Annabelle decides to team up with Ironhide against Sam, Wheelie, or the Twins.
- In the Star Wars fic ''It's a Jedi Thing, You Wouldn't Understand", Han and Luke are both annoyed about having to go to a diplomatic dinner with Leia. And they're acting worse than Leia's toddler twins. She catches them at the hotel in the midst of a water gun fight. When she interrupts them, Luke already emptied his on Han's head, and Han had his pointed at Luke's crotch, going for the "wet his pants" look.
- Done in The Lost Boys, using squirt guns filled with holy water against vampires. Unusually effective.
- Played for Wayans-style comedy in Don't Be a Menace to South Central While Drinking Your Juice in the Hood.
- From Dusk Till Dawn also has holy water guns, treated somewhat like Holy Hand Grenades.
- Attack the Block has this with "probs and mayhem," 2 nine-year-olds, using a water pistol full of petrol and a firecracker to burn an alien to death.
- The finale of Carry On Regardless was this. There were no water pistols and balloons but they were armed with garden hoses.
- Used in the final battle in Recess: School's Out, along with silly string, no less!
- In Flubber, Dr. Brainerd shows up at the Big Bad's house with a water pistol that he says he uses to lower the temperature of the flubber storage tank. In actual fact, the pistol is filled with a liquid flubber solution.
- In Lesbian Vampire Killers, the protagonists use water balloons made from condoms filled with holy water as weapons against the lesbian vampires.
- In Weird Science, Lisa threatens Gary's parents into letting their son attend a Wild Teen Party with a realistic-looking water gun, as she eventually reveals to Gary after she pulls it off.
- In Adventures of a Demon-Hunting Soccer Mom book 2, Eddie shows up with Power Soakers filled with tabasco sauce.
- Some mean upperclassmen in Paper Towns throw urine-filled water balloons at freshmen before Q intervenes.
- Shiro ends up with one in one of the The Adventures of Samurai Cat novels. Against a vampire.
- Harry Dresden of The Dresden Files once used water balloons filled with holy water against an attacking Black Court vampire.
- In The Nekropolis Archives, Matthew Richter carries a water gun filled with holy water for use against vampires and demons. Holy water is actually illegal in Nekropolis because of its potency as a weapon against certain Darkfolk.
- In the Doctor Who episode "The Fires of Pompeii", the Tenth Doctor uses a water gun against the lead Pyrovile.
- At the end of The Doctor, the Widow and the Wardrobe, Amy is carrying a squirt gun to hit annoying Christmas carolers when she opens the door and sees the Doctor. She squirts him because he's been away for two years.
- When Ross is trying to convince himself his student-girlfriend isn't too immature for him in Friends, he arrives at the dorm to find she's having a water-balloon fight. After they split up, he thinks "She handled that really maturely. Was this a mistake?" and then she drops a balloon on him from the window...
- In "The One Where Joey Moves Out", Rachel finds one of her bras in the guys' apartment and asks what the hell it's doing there. Joey explains that he and Chandler were having a water-balloon fight with some junior high kids and they used the bra to fling their balloons off the roof.
- MythBusters: one myth they tested was a combination of a water gun and a Static Stun Gun.
- Stargate SG-1:
- The episode "Bane" has Teal'c befriend a young girl who carries a Super Soaker* around. After she helps save him, he gives her a "superior model"* ...which she immediately uses to shoot Daniel Jackson. The good doctor remarks that maybe they shouldn't have loaded it. Teal'c answers if they hadn't, she would be unable to defend herself, before he pulls out an even bigger water gun* to chase after her.
- Played for Drama in "The Devil You Know". When Apophis interrogates O'Neill using a Fantastic Drug, O'Neill hallucinates that he's talking to his dead son Charlie. Charlie comes up behind Jack with a water pistol a friend gave him, but Jack gets angry at Charlie because he has a "no guns" rule.
Charlie: You have a gun.
Jack: That's different.
- The West Wing: after noting that Josh is the kind of guy who has to be hit over the head to notice that a girl is interested in him, Amy tosses a water balloon at him from the balcony of her office as he's leaving the building, that almost hit him in the head.
- One episode of Boy Meets World had Cory trying to earn enough money to buy a high-end squirt gun in time for an upcoming water war. After his dad helps him finish his job so he doesn't miss the fun, Cory ends up trading the new gun for two smaller ones, which he and his dad then gleefully turn on the rest of the family.
- On "And the Window of Opportunity", the second-season finale of 2 Broke Girls, Caroline and Max augment their verbal fight with the water-cleaning guns they're using.
- Used in multiple sketches of The Whitest Kids U' Know. The Water Balloon sketch is about a man selling water balloons in the old west and Booger Blasters is an advertisement for a variation of squirt guns that uses boogers. Both Booger Blasters and the Nerf Nuke sketch also mentions another product from the same in-universe company: the Cum Bomb.
- The prank that pushes the girls over the limit during "Prank Week" in Zoey 101.
- CSI NY featured an adult version called Water Gun Wars, based on the real life Streetwars game. Players try to 'kill' each other with water guns or balloons to become the last one standing in the game and win a cash prize. But one player got angry at the guy who knocked him out of the game and thought he'd pull a scare with a blank gun. He didn't know that blanks can be as dangerous as bullets at close range.
- The Mickey Mouse Club: One of the gong gags at the end of the theme song has Donald Duck being squirted with water pistols by two of his nephews, sending him on one of his trademark temper tantrums.
- In the video for Madonna's "What It Feels Like For A Girl", Madonna's character uses a realistic-looking water pistol on a couple of cops as she's going out on a violent joy ride with an elderly passenger.
- In the video for OK Go's "The One Moment", lead singer Damian Kulash gets hit on the head with two large water balloons, while rows of smaller water balloons pop in synchronized order behind him, in super-slow motion.
- Divas matches will sometimes feature these, especially during summer, for Fanservice like a Sexy Soaked Shirt. However, Jillian Hall once smacked Mickie James in the head with her water gun.
- Water Warfare is a Lighter and Softer First-Person Shooter based around water gun combat.
- zOMG!: the Heavy Water Balloon. Higher Rage Ranks will use larger balloons and slingshots.
- Adults seem keen to start water balloon fights in The Sims 2.
- Your starting weapons in Zombies Ate My Neighbors are water guns, specifically Entertech motorized water guns, although The game doesn't actually call them that. As most of your enemies are the undead, the guns are presumably filled with holy water.
- Eat Lead: The Return of Matt Hazard features these as the only weapons really effective against the Soak'em commandos. Hilariously, they're just as effective against every other enemy.
- Dead Rising 2 has normal ones and improvised ones that work like flamethrowers.
- Bully features water balloons. Not one of the stronger weapons.
- One of the power-ups you can shoot at your opponents in Re-Volt.
- Certain fire-based bosses in Dynamite Dux can only be harmed by water guns, which are always found right before the bosses in question.
- Splatoon is another Lighter and Softer First-Person Shooter, which uses guns filled with ink to attack opponents and claim territory.
- Super Mario Sunshine equips Mario with F.L.U.D.D.note , a high pressure water cannon with interchangeable nozzles. It comes in handy because a doppelganger of his has covered large parts of the island in a gunk like paint.
- Fallout 4's "Nuka-World" DLC has a water gun weapon called the Thirst Zapper. It normally fires harmless blobs of water until you find the Project Cobalt schematics, at which point you can modify it to fire weaponized Nuka-Cola at your foes, which cause explosions on impact.
- A number of Mega Man's acquired weapons have been water-shooters which often are strong against fire bosses. Mega Man (Classic) has Water Balloon (from Aqua Man) and Salt Water (from Neptune) while Mega Man X has Splash Laser (from Splash Warfly), Goo Shaver that sends small water waves along the ground (from Duff Mc Whalen) and Meteor Rain that sends a big water blob up which then goes down (from Rainy Turtloid).
- The Senran Kagura series has Peach Beach Splash, the installment that has the girls fight each other with water-based weapons.
- The Weird Autumn Edition of Night in the Woods has two minigames at Harfest, one of which involves throwing water balloons at the City Council of Possum Springs who pose as Halloween monsters respectively.
- Loserz once had a story arc about this.
- Ozy and Millie indulge in a few of these. Both involve Millie, a favoured target of the artist, and More Dakka.
- Housepets! had an entire story arc based on a water balloon war, "The Great Water Balloon War", between the titular creatures that was used to parody military and wartime tropes, starting here.
- Sam Starfall and Helix from Freefall have from time to time engaged in water balloon wars, often to the annoyance of Florence when she gets hit by a stray shot.
Sam: How can a species consider itself advanced if it's willing to travel between the stars and not bring water balloons?
- The Simpsons:
- Ed, Edd n Eddy: one episode involving the tree house has the Eds using water balloons. Another has them selling turkey basters as water squirters. Also Eddy's El Mundo Stinkbomb.
- Kick Buttowski: Suburban Daredevil: Kick and Gunthar fight Kick's older brother, Brad, for their hangout. Kick uses water balloons and Brad uses mudballs.
- Inspector Gadget has one of these equipped. For some reason.
- It's more like a miniature fire hose, and he's able to put out a fire with it quite handily. So that's probably the reason — putting out fires.
- Johnny Bravo episode "Balloon Buffoon" has Johnny and his friends trying to defend against youngsters armed with water balloons, which is treated by Johnny as a military campaign.
- Bob's Burgers:
- When the kids go trick-or-treating on the rich families' island in "Full Bars", they're warned about "Hell Hunt", where the local teens on bicycles terrorize the younger kids with, among other things, water balloons filled with pee.
- The season 5 finale "The Oeder Games" has Mr. Fischoeder baiting his tenants into a water balloon fight with the prospect of the winner not only being exempt from the rent hike, but getting a rent cut.
- Buster and Babs' story arc in Tiny Toon Adventures: How I Spent My Vacation begins with Buster going after a sunbathing Babs with a squirt pistol loaded with ice water. She retaliates with her own, resulting in an Escalating War of water balloons, kiddy pools, Babs opening the floodgates on a dam, Buster setting off a volcano with high explosives to create a tidal wave...
- Taken Up to Eleven in the Invader Zim episode "The Wettening". When Dib discovers that Zim is harmed by water, he uses his super-scientist father's lab to engineer more and more advanced water weapons. Once Zim discovers that he can waterproof himself with glue, he retaliates with a satellite-mounted balloon filled with all the water on earth.
- This skit from Wow! Wow! Wubbzy! takes this trope to extreme measures. Here, Wubbzy and Widget are playing "water-fight" by using water balloons, with each one seen getting bigger and bigger. Hilarity ensues and they later on begin using hoses, and a gigantic water-hose/water balloon combination, which eventually leads to the whole town ending up underwater.
Widget: [underwater] That wasn't supposed to happen!
- Recess: School's Out: During the final battle, the student body pummels Benedict's Mooks with water balloons and silly string.