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Living Gasbag

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Don't trust these guys, they're full of hot air.
"The giant air-floater from the dark elf lands. Only the brave dare to hunt them, only the strong survive them."
A netch hunter (on his quarry), The Elder Scrolls V: Skyrim — Dragonborn

Lightweight, floating creatures are a great way to dress up your Alien Sky, populate a gas giant or add to the curious fauna in a fantasy realm. Typically hollow, and filled with a light gas of some sort, these creatures usually resemble blimps or jellyfish or some strange hybrid. They may be large or small. If large, they may be used as transportation by the natives or colonists. If they're filled with hydrogen, expect them to be highly explosive.

They may drift aimlessly, but it's more likely that they can exercise some control over their flight, possibly with small wings, or by emitting puffs of gas. While they are primarily decorative, some may be useful, some may be dangerous, and a few may even be intelligent. If they're intelligent and hydrogen-filled, they will probably have a very rational fear of fire.

These creatures are most commonly found in a specific set of environments. Firstly, due to their highly alien and often bizarre appearance, they may be included the skies of alien worlds or lands to emphasize how different these places are from everyday Kansas skies. Secondly, they are often included in the fauna of places like gas giants or Worlds in the Sky, where no solid ground exists and all life needs to stay aloft.

Often overlaps with Starfish Aliens and Flying Seafood Special. Self-propelled forms employ Bizarre Alien Locomotion. May count as a Giant Flyer. May double as a Living Ship, in which case it's probably also a Cool Airship or even an Airborne Aircraft Carrier. Compare Space Whale and Zeppelins from Another World. May provide Balloonacy.

Definitely not to be confused with Gasshole.


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    Anime & Manga 
  • 2001 Nights: In the second episode, "Symbiotic Planet", one of the colonists on an alien planet has been studying some floating spheres, and feels he may have made friends with some. This is later proven to be true when a group of them sacrifice themselves to protect his colony from incoming missiles.
  • One Piece: "Sky Fish" are fish that live in the clouds (or, more specifically, the "white sea"), having become flat and floaty in order to adapt to the environment, where the "water" offers less resistance. They're literally living gasbags as they pop like balloons when pierced. An example is the "takoballoon" (English: "octoballoon") who appears at the end of the Skypiea saga to safely lower Going Merry to the Blue Sea.
  • The Junji Ito Kyoufu Manga Collection story "The Hanging Balloons" features a very odd take on this trope. Giant living balloons, each one bearing the likeness of a specific person's face, suddenly appear all over the world, hunting down the people they look like and strangling them with their strings. The balloons are easy enough to destroy, but doing so kills the person they are "connected" to as well.

    Comic Books 
  • Black Moon Chronicles: On the second Earth Wismerhill's men run into miles-wide flying jellyfish that are either giant colonies of smaller jellyfish, or the smaller ones are the brain cells of a single being.
  • Sensation Comics Featuring Wonder Woman: In "Venus Rising", Wonder Woman accompanies a scientific expedition to Venus, where she and the scientists are surprised to find giant dragon-like living gasbags which seem intent on tearing apart their vessel.

    Films — Animation 
  • Battle for Terra: Pretty much all the native life on Terra consists of this, including its sapient inhabitants the Terrians.
  • The Flight of Dragons: Dragons fly by digesting limestone to make hydrogen and thereby inflating themselves like blimps. The wings are simply to steer. This is also how they breathe fire, meaning that a dragon who breathes out too much flame will remain grounded until it has the time eat and digest more stone.
  • A deadly, predatory pterodactyl in Ice Age: Dawn of the Dinosaurs has himself become one unintentionally.
  • Titan A.E. has a plant version, filled with hydrogen.
  • A Tree Of Palme: The (apparently alien) planet is inhabited by a lot of floating jelly-fish like things. One type are referred to as "grass" and they may be the equivalent of plants, though there are also some earthly plants on this planet in a few places.

    Films — Live-Action 
  • Dogora is a Japanese kaiju film involving diamond thieves and a giant space jellyfish that happens to eat carbon (including diamonds).
  • In Men in Black 3 the Boglodites (the Big Bad's species) invade the Earth with what appear to be armored Eldritch Abominations with fleshy underbellies covered in large pulsating blisters that suggests that they're Living Ship gasbags.
  • In Nope, it's revealed that the true form of Jean Jacket is a massive, billowing, jellyfish-like creature whose insides resemble inflated tubes. Emerald is even able to kill it at the end by popping it like a balloon.

  • Alien in a Small Town: It's something of a throwaway detail, but the story makes passing mention of bioengineered "bioblimps", which are literally living blimps used for transportation. Apparently they're long out of fashion by the time of the story, but Indira notices one passing overhead and speculates on how old it may be.
  • Ares magazine #2 article "An Exozoological Sampler": The Baloonalo is a 100 meter wide spherical alien creature that lives in the atmosphere of a gas giant planet. It creates, heats and stores hydrogen inside itself to provide buoyancy.
  • Arthur C. Clarke's had a couple of examples:
    • "Meeting with Medusa" features the discovery of a miles-long jellyfish-like creature floating in the atmosphere of Jupiter. (In biology, medusa is a term applied to certain forms of jellyfish.)
    • The Space Odyssey Series: 2010: The Year We Make Contact has the noncorporeal Bowman journeying down through the Jovian atmosphere, where he sees gigantic living things in various geometric shapes floating through the clouds and consuming similar smaller creatures.
  • Ciaphas Cain: An offhand comment in Death or Glory mentions skywhales, which the accompanying footnote explains as a creature from Blease's World that lives on airborne pollen and produces hydrogen gas as a byproduct of its metabolism. The creatures are quite placid and the planet's human inhabitants have domesticated several subspecies to turn them into Zeppelins from Another World.
  • Cryptozoologicon: In Volume 1, the mysterious "Flying Rods" sometimes seen in photos and videos (actually just badly exposed moths) are imagined as "workers" for a floating Hive Queen resembling a transparent living blimp who lives her entire life hidden in the clouds, and descended from relatives of anomalocaridids.
  • The Culture:
    • Look to Windward: Dirigible Behemothaurs are possibly the largest living creatures in the setting. They inhabit Airspheres, vast areas of space that maintain a consistent atmosphere inside them. Entire ecosystems of other lifeforms can exist on a Behemothaur, and anyone trying to harm one of them get utterly annihilated by protective energy beings from another dimension.
    • Matter: The Xinthian Tensile Aeranothaurs are stated to rival the Behemothaurs in scale, and their name and description suggests a similar lifeform, however the relationship between the two, if any, is unclear.
  • David Brin has used this more than once:
    • Glory Season has the zoor, flying jellyfish-like creatures which range from twenty meters up. Sailors like to tie ribbons and messages to their tentacles, and the larger ones can lift a child.
    • Uplift: The Bahtwin were uplifted from a lighter-than-air gasbag species that floated in their homeworld's atmosphere.
  • Expedition, and the Speculative Documentary based on it, Alien Planet, feature the many alien species which float above the ground in Darwin IV. One example is the almost-sapient Eosapiens.
  • The Flight Of Dragons: Peter Dickinson reimagines, well, dragons in this way. He postulates that large internal hydrogen compartments explain not only the flight of dragons, but their fire-breathing (venting excess hydrogen and then igniting it), legendary toxicity (the internal biochemistry needed to generate the hydrogen would be rather corrosive), and even treasure-hoarding (when you constantly sweat acid, you need something chemically inert, e.g. gold, to nest in).
  • Gaea Trilogy: The Blimps, floating sapient creatures which live inside of the Living Planet Titan, and often serve as a means of transportation. The one known as Whistlestop gives our heroes a ride in the first book.
  • In The Horror of the Heights by Sir Arthur Conan Doyle, a luckless aviator stumbles onto a whole high-atmosphere ecosystem of diaphanous floating organisms, many of which are similar to giant jellies. At least one of them has large bubbles that are filled with a light gas that keeps it in the air.
  • Interstellar Pig by William Sleator has a gas-filled flying octopus.
  • Larklight: Jupiter is home to a number of such beings, including floating pig-like creatures domesticated as essentially floating algae scrubbers to keep homes clean and gigantic air whales, which resemble hydrogen-filled, multi-eyed living blimps far more than they do actual cetaceans.
  • The Leeshore by Robert Reed takes place on a planet completely surrounded by biological gas bags so densely that sunlight almost never reaches the surface — the only sunlight is around the only settlement's decrepit Space Elevator, as its point defenses blast any approaching gas bags.
  • Leviathan: Huxleys are floating jellyfish-creatures used for (slow) transport and scouting missions. So, who's up for being hoisted aloft by a living weather-balloon that vents its gas when frightened? The Leviathan itself is also a genetically engineered organism, primarily derived from a whale, that's filled with air sacs so it can be used as a biopunk zeppelin.
  • Medea: Harlan's World: One of the alien races created for Harlan Ellison's shared world project Medea was a gasbag filled with hydrogen that could float through the air.
  • In the sequel to Fragment, Pandemonium, some of the inhabitants of the titular subterranean ecosystem are jellyfish-like molluscs which float through the air by means of a chemical reaction inside gas bladders which produces hot air, creating lift. These range from swarms of flitting "nudibats", to the venomous and predatory "firebombers", and the gigantic "blimp-whales", the undisputed apex predator of Pandemonium.
  • Perry Rhodan, alien-wise, has everything but the kitchen sink. In a reader cartoon, a living balloon tells his life. In a royal Downer Ending, his question for the meaning of life and everything answers with a: -pop-
  • The Red Tape War: One of the three beings named Millard Fillmore Pierce is a sapient floating gasbag who is checking out our universe with an eye towards invasion.
  • Shards of Honor opens with a survey of a newly-found planet among whose fauna are a particularly vivid (and gruesome) species of air-jellyfish. They land on herbivores and suck their blood, their transparent envelopes looking like wine-glasses as they fill up. Since they float using hydrogen, the protagonists are also able to use one as an improvised bomb.
  • Star Carrier: The H'rulka are a race of colony organisms (think Portuguese man o' war) that live in the upper atmospheres of hydrogen/helium gas giants. The colonies form floating organisms upwards of 200 meters long.
  • Starman Jones: The floating gasbag aliens (which the humans call "hobgoblin balloons") are used by the centaur aliens as spies. They are capable of moving on their own, not just drifting on the wind.
  • Star Wars Legends: Beldons, creatures resembling titanic, bulbous jellyfish, native to Bespin float in the gas giant's upper atmosphere and produc Tibanna gas.
  • The Sunborn, by Gregory Benford, has strange alien gasbags discovered on Pluto, which show signs of intelligence.
  • The Stormlight Archive has the Unmade Re-Shephir, the Midnight Mother. She is essentially smoke wrapped in a preternaturally tough membrane capable of sprouting teeth.
  • In The Tin Woodman of Oz, the main characters encounter a Wacky Wayside Tribe of balloon people called Loons, who inhabit a town called Loonville. When they turn hostile, the characters defeat them by popping them with needles, reducing them to empty bags of skin.
  • In Wheelers, there's a sapient species called 'blimps' living in Jupiter's atmosphere, maintaining their buoyancy with 'liftgas'.

    Live-Action TV 
  • Alien Worlds (2020): The skygrazers' predators raise themselves into the sky by using symbiotic microorganisms to inflate large sacs in their abdomens, allowing them to float like balloons until they're high enough to ambush skygrazers flying below them.
  • Cosmos: A Personal Voyage: In one episode, Carl Sagan theorizes that life existing on a gas giant planet such as Jupiter would be most likely to evolve into this form.
  • Extraterrestrial (2005): The balloon plants are a vegetal example of this. They consist of a number of large hydrogen-filled sacs connected to a central stem by tendrils, which raise the plant above the canopy of the immense pagoda trees. Mature sacs eventually break off and float into the sky, drifting for vast distances until fire or lightning burst them and scatter their seeds.
  • The Outer Limits (1995): In "Tempests", kilometer-long jellyfish blobs float through the clouds of the planet Leviathan.
  • Ultra Series:
    • Ultraman Ace: The kaiju Bad Balloon is a living hot air balloon which can alternate between the forms of a harmless balloon, or a giant balloon-themed monster. It uses its balloon form to abduct unsuspecting children and drain them of their souls, leaving behind kids as emotionless shells of their former selves.
    • Ultra Q: The title creature in "Balloonga" is a blimp-like creature from Saturn that can expand ad infinitum as long as it has a steady supply of energy.

    Tabletop Games 
  • Arduin: Airsharks have hydrogen gas bladders that allow them to swim through the air the way normal sharks swim through water. Fire-based attacks against them can cause them to explode in a fireball that is 5 feet in diameter for each 10 Hit Points the airshark has.
  • Blue Planet: Blimps (Giordana fluitarus) are regularly spotted in the skies of Poseidon, thanks to their bodies growing up to 40 meters long. They're a considerable nuisance, for all the reasons you'd expect from a hydrogen-filled Portuguese man-o'-war.
  • Chaosium's supplement All the Worlds' Monsters Volume III: The Four Eyed Hig is a cube-shaped monster filled with helium that grants it neutral buoyancy. Each face of its body has an organic propeller to move itself around.
  • Cyborg Commando: The Xenoborgs (alien invaders) can split water into hydrogen and oxygen. They can store the hydrogen inside themselves and use it to rise into the air and achieve limited flight.
  • Dungeons & Dragons
    • The gas spore is a floating, spherical fungus that contains high-pressure, buoyant gas filled with spores and explodes if hit. They bear a strange resemblance to beholders, and can be found in beholder lairs to serve as guardians and decoys.
    • The lurker above is a large (20 feet wide) monster that generates a gas in sacs in its body that give it neutral buoyancy. It uses its large "wings" to fly around.
    • Decaton modrons can create a lighter-than-air gas inside their bodies that allows them to rise into the air and fly at a slow speed.
    • Soarwhales are floating creatures that resemble baleen whales, docile enough to serve as living blimps that carry gondolas or howdahs for passengers or cargo. They also have a unique defensive mechanism, a "breath weapon" attack that involves releasing a cloud of their buoyant gas — the soarwhale rapidly drops 100 feet before stabilizing, while everything in the area it previously occupied must make a Fortitude save or become paralyzed for about half a minute, usually a very bad thing when you're a mile off the ground.
    • Dark Sun has Floaters, a species of sentient (if somewhat dumb) hydrogen jellyfish. If hit by fire-based attacks, they take quadruple damage and have a 75% chance of exploding like a blimp filled with hydrogen.
    • Dragon magazine "Dragon's Bestiary":
      • Issue #52: The Pelin is a large aerial creature that extracts hydrogen and helium and uses it to float, much like a zeppelin.
      • Issue #58: The Sull is a large creature that looks like a flying saucer. It floats by using buoyant gasses created by its digestive system and stored in its central hump. It moves around by sucking in air and spraying it (and its buoyancy gasses) out in the appropriate direction.
    • Dungeon magazine #70 adventure "Kingdom of the Ghouls". The cloakers have beasts of burden called "floaters". Floaters are gigantic floating gas bags filled with an explosive gas (probably hydrogen).
    • Forgotten Realms: The xantravar is a monster that stores hydrogen gas in flotation chambers in its heads. It takes in or expels the gas to rise or sink. The gas can be expelled in specific directions, thus acting as a steering jet. If the gas contacts fire it will burst into flames, burning anything within 10 feet.
    • Spelljammer: Holbags are gigantic (up to 10 miles wide) gas-filled balloon-like creatures that float in the atmosphere of the planet Alabeth.
    • White Dwarf magazine #9, article "The Fiend Factory": The flying fish is a large lungfish that breaks up water to obtain hydrogen gas, which it stores internally and uses to float in the air. It continually leaks hydrogen, and any nearby open flame can cause an explosion.
  • Lords of Creation: The Heroes article "Survival Run of the Starnomads" describes Stinger-Spear Squids, alien creatures that contain sacs filled with helium gas, allowing them to float in the air. They have tubes that blow out helium and propel them.
  • Pathfinder: The solar system where the main setting is located also contains the gas giants Bretheda and Liavara. These are home to the barathu, gelatinous creatures vaguely resembling a cross between a jellyfish and sea squirt, with no discernible external features save for trailing clusters of tentacles and several hydrogen sacs for flotation, who lead mostly nomadic lives in the endless skies of their homeworlds. In Starfinder the Brethedan barathu have carved out a niche in the Pact Worlds as masters of Organic Technology, often taking advantage of their ability to merge with one another to form a unique form of Mega-Corp.
  • Rocket Age: Jovian Gasbags are gigantic jellyfish-like organisms that float in the upper atmosphere of Jupiter, feeding on whatever passes by them. The Saturnian Krakens are possibly this, but since very little is known about them no-one is certain.
  • Star Frontiers: Volturnus: Planet of Mystery describes the air whale, an alien creature that produces hydrogen as a byproduct of digestion. The hydrogen is stored in sacs inside its body and provides the lift that allows it to float. It maneuvers by venting compressed hydrogen through tubes.
  • TORG: The stalengers of the Living Land are floating, gas-filled beings with manipulative tentacles.
  • Traveller
    • Journal of the Travellers' Aid Society:
      • #17 "Contact: The Jagd-II-Jagd": The Jagd-II-Jagd are an intelligent alien race that live in the atmospheres of gas giant planets. They have spherical bodies filled with a number of compartments. They absorb hydrogen and other gasses from the gas giant's atmosphere, store them in the compartments and use them for buoyancy and propulsion.
      • #18 "The Bestiary": The Luugiir are aliens who look like small hot air balloons . They convert sunlight into electricity and use it to obtain hydrogen from water. They store the hydrogen in their gas bag, which causes them to float in the air. They have a maneuvering jet that expels air and allows them to move in a specific direction.
    • Challenge magazine #27 "Bestiary": The adult Oegongong aliens use a biological form of electrolysis to generate hydrogen from seawater. They use it to fill the sacs on their back: when the sacs become huge and balloon-like they float into the air and travel over the land where they drop their eggs.
    • FASA's supplement Rescue on Galatea: On the title planet lives an aquatic alien creature called the muqath, which is like a jellyfish with a shell. It has sacs filled with lighter-than-air gas that it uses for flight.
    • Spacefarer's Guide to Alien Monsters
      • The floater is an alien creature whose body is a bag containing hydrogen gas, which allows it to float through the air. It has electrically charged tentacles which descend below it. The tentacles stun any creatures they touch and drag them up to the floater to be eaten.
      • The lanceballoon's body is an oval-shaped gasbag filled with helium, which allows it to float in the air. It has fins that look like sails to steer. The tentacles that hang down from it have embedded prisms that it uses to focus sunlight and use it as a weapon.
      • The sharkoid is shaped like a fish and swims through the air, supported by multiple hydrogen-containing cells in its body.
    • Spacefarer's Guide to Alien Races. The Harundali are a race of aliens shaped like jellyfish who come from gas giant planets. They can store hydrogen in their bodies and use it to float in the air.
  • Universe: In the list of encounters in the adventure guide, alien #28 has a balloon-like gasbag body with 6 two-foot long tentacles hanging from it. It is a Plant Alien that maintains buoyancy by producing lighter-than-air gasses inside its body out of air and sunlight. It propels itself by squirting gasses out its underside.
  • Maps Book 1: Cities. Lifudars float through the skies of the gas giant moon Ahijad using the lighter-than-air gasses stored inside them. They look like a pair of small blimps joined together, with tendrils descending below them.
  • Warhammer 40,000: Tyranid bio-beasts include spore mines, floating bags of acid, explosive and tentacles that double as sentries. They are drawn to the enemy, swarming in numbers. Other beasts can transport them, release them over the battlefield, or launch them like living mortar shells. A much larger variety is the Meiotic Spore, big enough to take down large aircraft with a single blast.

    Video Games 
  • Adventure To Atlantis: One of the monsters you can encounter is the Air Squid. It fills itself with lighter-than-air gasses and floats around. When it encounters a potential victim it descends and attacks with its tentacles.
  • The final stages of Akuji the Heartless are set in a floating, abandoned pirate ship sailing through the infinite abyss of the cosmos. The ship itself is infested by various floating octopoid monsters such as alien jellyfishes capable of stinging the player with tentacles and floating one-eyed blobs who can shoot energy balls.
  • Chaos Heat have the mutant spore enemies, floating flesh sacs containing a single red nucleus visible through it's semi-transparent skin. These are Action Bomb creatures who explodes themselves when you're in range.
  • Command & Conquer: Tiberian Sun: Firestorm has Tiberian Floaters, mutated lifeforms that look like giant jellyfish who release tiberium gas as a form of propulsion and attack with electric shocks. They're also incredibly dangerous and very annoying.
  • Dragon Quest has an enemy named the Gasbagon. It's a monster in the dragon family which is inflated like a balloon. Because they're filled with fire and explosive gasses, they often end up using Kamikazee attacks. There is also a tougher version called the Noble Gasbagon.
  • The Elder Scrolls:
    • The Elder Scrolls III: Morrowind has the Netch, giant flying jellyfish that provide the page image. Males ("bull netch") are larger with leathery brown hides, and can shoot poison. Females ("betty netch") are smaller and translucent blue in color, with stronger physical attacks. The native Dunmer (Dark Elves) domesticate them and use their hides as leather.
    • The Elder Scrolls V: Skyrim: Netch return in the Dragonborn DLC, having drifted from Vvardenfell to Solstheim after the Red Mountain erupted.
  • The Eternal Cylinder has the Onkifirt, a predatory flier found on the Trebhum's world. It's surprisingly agile, but also dumb enough that it can be tricked into incubating Trebhum eggs.
  • Evolve had a creature in its earlier stages of development called the Magma Wyrm that feeds on ignimbrite crystals as a larva, filtering out the hydrogen into a ballast sack to float as an adult. Unlike most examples, their store of ballast is limited by the amount they consumed as a larva and they eventually run out and sink to the ground where they're easy prey.
  • Final Fantasy XIV: The jellyfish monsters float this way according to Word of God.
  • Gears of War 3 introduces the Locust Gas Barge as a means of transportation after the flooding of the Hollow.
  • God of War Ragnarök: The Hafgufa are gigantic blue jellyfish that used to float through the skies above Alfheim's deserts. They've long since been buried under the sands, trapped by the Dark Elves hive matter and scared into kicking up the awful sandstorms that make the desert nigh uninhabitable.
  • Half-Life: A Xen creature called the "Flocking Floater" was scrapped from the game before its release. Originally, groups of these would drift benignly in the sky. When shot, though, they would fire gas at you until killed, making the gasbags on their heads deflate upon hitting the ground.
  • Halo has the Engineers/Huragok, an artificial race of Gadgeteer Geniuses who resemble a large purplish floating gas-bag with a blueish tentacled slug sticking out of it. Interestingly enough, they're named after how buoyant their gases were at birth, eg "Lighter Than Some", "Prone to Drift", "Requires Adjustment", etc.
  • Kirby is normally not a gasbag, but he can turn into one by inhaling air and flapping his stubby arms. King Dedede can do the same.
  • The Legend of Zelda: A few games portray octoroks, a recurring kind of octopus-like enemies, like this.
    • The Legend of Zelda: A Link to the Past: A Unique Enemy on the east coast of Lake Hylia, called the octoballoon, resembles a bloated octorok floating a short distance above the ground.
    • The Legend of Zelda: Breath of the Wild: Water octoroks are normally aquatic, but they can float through the air when changes in barometric pressure cause gases in their bodies to inflate, swelling them up like balloons and lifting them out of the water. Sky octoroks float all the time, thanks to lighter-than-air gases filling their mantles. All octorok types will drop their internal flotation bladders when slain, which if attached to objects will automatically inflate and lift their burdens into the air.
  • Mass Effect: Eden Prime has "Gasbags" as part of its local wildlife, being completely harmless according to Jenkins. The tutorial has you optionally use one for target practice.
  • Master of Orion III adds a class of races called "Etherians" to the series, consisting of two races, the Eoladi and Imsaeis, who inhabit gas giants. The Eoladi are whale-like gas bags, while the Imsaeis are more like gigantic gaseous jellyfish.
  • Meteos has a few: The puffy inhabitants of Yooj, the sentient colorful gas clouds of Brabbit, the umbrella-like fellows from Megadom, and the creatures of Bavoom that drift endlessly in the planet's fierce winds. All of these civilizations live in either nebulae or gas giants and must float by necessity.
  • Metroid: Many of the organisms in the games float this way. It is unclear if the titular Metroids use gas bags, or are floating through some other, more mysterious means.
  • Monster Hunter 2 (dos): Yama Tsukami is a gigantic Elder Dragon that appears to be a hybrid between a floating forest and an octopus. Despite its size and weight, it's capable of traveling airborne thanks to an internal gas produced by its biological system to facilitate floatation.
  • NetHack: The Gas Spores from Dungeons & Dragons also appear here, and they are the bane of all leeroys.
  • Ori and the Will of the Wisps's Silent Woods has insectoid balloon enemies appropriately called Floaters, which explode on contact.
  • Pikmin:
    • Puffy and Withering Blowhogs are floating, air-filled creatures resembling nothing so much as colorful party balloons with fins, eyes, short trunks and series of holes down their sides. Their main attacks consist of blowing gusts of air out of their bodies to blow your Pikmin about, and they deflate when they die, swiftly shrinking to a fraction of their former size.
    • Jellyfloats are essentially hovering, air-filled jellyfish that suck up their prey rather than sting it. The Medusal Slurkers that replace them in Pikmin 3 work much the same way, with the addition of a dandelion-like puff sprouting from their tops as an extra flotation device.
  • Pokémon has several examples.
    • Drifloon and Drifblim are living floating balloons, and despite having a largely nonthreatening appearance, the former are known to abduct children (or try to anyway: they're not nearly strong enough to lift a child off the ground). Drifblim is mostly peaceful, however.
    • Koffing are spherical floating bags filled with toxic gases, with pores all over them for releasing those gases. Its evolved form, Weezing, is two Koffing fused together.
    • The Jigglypuff line is a subversion; though gasbags, they don't fly. (Except in the anime. In a few episodes, Harley's Wigglytuff does get airborne, though he has very little control once up there.) In Pokémon GO, Jigglypuff does have a very "floaty" jump, giving it a rather slow descent whenever it does so.
  • Prey (2006) has strange floating gas-bag creatures that spit acid living inside of The Sphere.
  • Schizm: Mysterious Journey has an entire level filled with these. Some of them have mechanical attachments that you can interact with, and one uses a gas from the atmosphere to fill up small blimps for transportation.
  • Shadow of the Colossus: The thirteenth colossus is a giant flying worm with dragonfly like wings that clearly don't do enough to keep it airborne. It also has large gas sacks which it presumably uses for lift, since shooting them with arrows deflates them and brings it down low enough for you to reach.
  • In Star Control, the Slylandro are floating translucent gas bags with glowy bits inside them. If you call them gas bags in dialog, they return the (friendly) insult by calling you a human fluid sack.
  • StarCraft: The Zerg Overlords are helium-filled gasbags that move with psychic power. They can carry other Zerg, and their psychic ability is required for controlling a swarm. StarCraft II adds Overseers, an evolution of Overlords, and Corrupters, who also seem to work on the gasbag principle.
  • Temtem: Fomu is filled with steam, which it uses to propel itself around instead of walking. When it evolves into Wiplump, the steam forms a pair of wings. Also, Kaku has pockets of air in its body that allow it to drift on the wind.
  • Turgor: Brother Montgolfier may or may not be this: the upper half of his body sticks out of a giant balloon, and nothing is known what did he look like before he was forced to alter his body, just like the rest of the Brothers. If you challenge him to a fight, be prepared that his balloon is not just for flying: in a pinch, he will purposely crash down on the floor, causing an explosion so huge you won't be able to survive it without protective sigils.
  • Unending Dusk have a red, floating gasbag enemy which can damage you with it's body spikes. If left idle for too long, it will deliberately inflate itself and explode as an Action Bomb dealing extra damage.
  • Unreal has Gasbags and Giant Gasbags, basically balloons with tiny arms and big eyes, which float towards you slowly and shoot fireballs.
  • Xenoblade Chronicles X: Most of the flying critters in the game clearly have gas sacs keeping them aloft, ranging from the man-sized floating jellyfish to Giant Fliers like Colubrims. Even the land-bound Millesaurs (utterly enormous dinosaur things) are noted to have huge gas bags in their bodies, lightening them to the point they don't collapse under their own body weight.

  • Schlock Mercenary: The Oafa are giant, sapient sacs of hydrogen gas who use artificial speakers to communicate. Interestingly they use the same Galstandard Peroxide dialect as the aquatic Schuul.
    Footnote: The "lift-breath" in question is molecular hydrogen, H2, which is extremely flammable in oxygen environments. The evolutionary path that led the Oafa (oh-ah-fah) to become, essentially, explosive blimps, is a fascinating one involving a metal-rich water world, acidic tentacles, tasty jellyfish, and a happy accident allowing escape from the appetites of everything that cannot fly.

    Web Original 
  • Mortasheen has the Miasmadusa, which is something like a gas-filled Man 'O War and can rain down deadly toxins on their opponents.
  • SCP Foundation
    • SCP-312 ("Atmospheric Jellyfish"). It's a large jellyfish-like creature that floats in the air by heating atmospheric gasses within itself. It can release water vapor and control air currents to create a cloud around itself as camouflage. It hunts humans and floats above them. If the human looks up at the creature it will suck the human up into itself with a wind vortex and consume it.
    • SCP-1158 ("Arboreal Jellyfish Puppeteers"). SCP-1158 is an airborne, carnivorous predator that resembles a large Portuguese man-o-war (jellyfish). It floats using hydrogen produced from bacterial decay.
    • SCP-1308 ("Hungarian Floater"). SCP-1308 has a number of internal cavities filled with hydrogen gas. It propels itself by flapping its body using muscular contractions.
    • SCP-1784 ("Skywriter Sloths"). The sloths use electrolysis to break down water into hydrogen and oxygen. They store the hydrogen in an internal bladder and use it to float in the air. They store the oxygen and use it to supplement their breathing at high altitudes.
  • On several entries in this blog, the writer closely examines the physical possibility of living gasbags (or as she calls them, "ballonts"). In short, a ballont would need to be very large to get afloat in an Earth-like atmosphere in Real Life; a ten-metre wide hydrogen gasbag could lift around 500kg, which would account for its organs and limbs. This poses problems for how such a creature would reproduce, since living gasbags are inefficient below a certain size. Thus, the author concludes that living gasbags are unlikely to evolve on Earth-like planets. The most suitable environment for a realistic floater to develop would be a large terrestrial planet, with high surface gravity, and an atmosphere rich in heavy gases (in other words, something like Venus).

    Western Animation 
  • Samurai Jack: In "Jack Under the Sea" Jack arrives to the Triseraquin Underwater City after being swallowed by a sea creature that has a transparent oxygen bag serving like an organic submarine.
  • Star Wars: The Clone Wars:
    • The Bounty Hunter Derrown, a member of the Parwan species. Parwans are humanoid fungi with tentacle-like limbs and filled with buoyant gas that lets them float.
    • The Octuptarra Combat Tri-Droid is based off of the octuptarra, a Living Gasbag which lives on the planet Skako.
  • StarCom: The U.S. Space Force: The jellyfish-like Airwhales of Jupiter feature in one episode.

    Real Life 
  • Although no known animal or other creature can float in the air in this way, one animal uses this trick to float on water: the Portuguese man o'war. This animal is actually a small colony of smaller animals called zooids, each of which relies on the others for some function. They collectively form an inflated "sail" containing a mixture of carbon monoxide and regular atmospheric gases, which allows them to float on the surface of the ocean, where they catch prey. This may be the inspiration for some of the fictional creatures under this trope.
  • "Atmospheric Beasts", types of cryptids that are this trope incarnate. Whether they're real has yet to be proven, but in general, they tend to look like giant flying versions of the above mentioned Man O' War.
  • Aeroplankton do exist, though they're simply microscopic or very small organisms of all phyla either passively borne on air currents or using wind to navigate, and none of them do it on wings or internal gaseous bladders (not that they need to, for their size). The biggest examples would be spiders using silken balloons to travel, and they can be borne several miles from their point of departure.
  • As commented above, scientists such as Carl Sagan have suggested Living Gasbags could thrive on gas giant planets such as Jupiter. He even thought on the types of "floaters" that could exist and on the ecological niches they could inhabit.note