Air Vent Passageway / Video Games

Air-Vent Passageways in video games.

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• One level of 24: The Game has Kim Bauer, armed only with a taser, having to crawl through ducts to get around a room full of bad guys. She has to move very slowly, though, or they'll hear her and shoot.
• Aka Manto: You can use the vents to move around in the school. Just watch out for the MASSIVE centipede.
• Most videogames based off the Alien franchise will naturally have this option accessible for both Alien and human characters at some point, but special mention should be made for Alien: Isolation, where this method of getting around becomes the standard once Sevastapol has gone to hell, both to avoid Working Joes and violent civilians. They're noisy to open and move around in, which will draw the xeno's attention; they're dark as hell and can have multiple dead ends; they disrupt your tracker and make it impossible to know if the xeno is nearby; and if the xeno gets in with you (which it will), you'd better hope you had the sense to bring a molotov.
• Aliens vs. Predator 2 featured liberal amounts of duct crawling. The first few levels of the Marine campaign required constant duct crawling, including a situation where Frosty has to jump into a duct vent that a Xenomorph recently launched out of in order to avoid being eaten. The Alien campaign, however, was almost entirely composed of duct jumping for most of the early half of the game.
• Alien Quarantine: If a door is closed, Jason may need to crawl through a vent filled with enemies to proceed. He can't fight back inside, though.
• Among Us: The Impostor can travel through vents to travel to locations far faster, or enter/escape locked rooms. Just be wary of other players seeing you do this, because it's as dead a giveaway as it gets barring killing someone right in front of them. However, as of one of the latest updates, Crewmates can enter and exit vents as an Engineer.
• Danny in Angels of Death, after initiating the building auto-destruction and the stairs just couldn't be an option. He appears out of nowhere and shoots Rachel.
• ANNO: Mutationem: When searching for an informant at Noctis City, Ann finds the informant's local spot guarded, and upon searching around she finds a nearby air-vent that uses to slip past the guard.
• Anti Villain has some in the facility Rory has to escape to prove himself as a villain initiate. A bulletin board notice from management states that employees should stop using them due to safety issues, no matter how fun it is.
• Armored Core has the player chase after terrorist mechs who have escaped through air tunnels. In two-story tall mechs. It's sort of justified, as these are the vents that are supposed to serve an underground city. Just don't think about how that would actually work.
• In Banjo-Tooie, Grunty Industries contains a few unusually spacious air vents. Banjo, Kazooie, Mumbo and even the level's washing machine transformation can casually pass through them.
• This happens a lot in Batman: Arkham Asylum. Whenever opening doors, stealth or jumps are impossible, a conveniently placed vent will always be there to be busted open to save the day, and help you proceed. Sort of justified by the fact that Arkham Asylum is famous for having horrible security. Also, many of the buildings in Arkham are very old (the asylum as a whole dates back to the mid 19th Century), so the vents are likely from an old ventilation system. Every building in later Arkham games got their air vents from the same contractor, especially when there's a Predator mission in the building.
• Battlefield 2142. The Titans have vents on the top that provide an alternate way to enter, however, unless the other team if full of idiots, they are usually boobytraped or being guarded by someone armed usually with a shotgun or a LMG.
• Lots of duct-crawling goes down in Beyond Good & Evil. Jade makes use of air vents once or twice in order to break into a few facilities, but Double H tends to do it whenever he and Jade split up in order to follow her. He slides out of one during the third boss fight, rocketing to the rescue.
• Bioshock Infinite, Burial at Sea DLC. Elizabeth can use air vents to access areas not available to normal travel and avoid enemies.
• Blame Him: To get back to the lockers from the room with the first enemy in the game, the Player Character needs to crawl through a vent.
• Blood Breed: One section of the game requires the Player Character to crouch through an air vent to continue because the door next to said air vent is boarded up.
• Call of Duty:
  • Though technically not an air vent, one mission in Call of Duty 2 involves a group of Russian soldiers infiltrating a German-held railway station via a long, damaged fuel pipe. The Germans are quick to catch on, though, and if he player isn't careful he can get caught by gunfire or hand grenades.
  • In the final act of Call of Duty 4: Modern Warfare, you infiltrate Zakhaev's missile base through the vent system.
• In Chrono Trigger, you can sneak around the Blackbird by using airducts. Or you can bring Ayla to your party and avoid the issue of lacking weapons altogether.
• There is a more justified example in Code 7; there are no humans sneaking through air vents. The EIU agents own Muffin, an infiltration drone created for that purpose. Usually Rabbit is the one that programs them, but since he’s currently injured, it’s your job to guide them. You do this by writing simple code with commands such as go forward, turn left/right and press button, while loops and if conditions.
• Contagion (Monochrome) has them in the Escape map, Roanoke Police Department. Zombies can use them as shortcuts to get through different parts of the map.
• Some Counter-Strike maps feature this. E.g. on cs_assault, there is a large air vent that leads from the hangar roof to the room with the hostages. Appropriately, walking through it makes a lot of noise and it can be shot through to kill whoever is inside.
• In Dark Fall 2 Lights Out, Parker must crawl through an air duct to reach the future-era laboratory complex. As he must navigate the high-tech duct system using a 1910s bullseye lantern to illuminate his path, it's a real Anachronism Stew of a scene.
• The Darkside Detective:
  • In the chapter "Police Farce", McQueen accidentally breaks a section of air duct in the precinct house while attempting to mend it. He remarks that if anybody asks him what happened to it, he's going to claim it was broken by a maverick police officer crawling around inside the duct.
  • McQueen gets to do some actual duct-crawling in the Christmas Episode, as part of a shout-out to Die Hard.
• Dead Rising has Frank West use air vents as passages to and from the safe rooms, as Otis welds the actual door shut to keep the zombies out. As Dead Rising takes place in a mall as well, it's likely a homage to Dawn of the Dead (1978).
• Dead Space
  • The ship in which the game takes place is blanketed with enormous, easy access vent shafts that the Necromorph enemies use to move around at will. This allows them to bypass security lockdowns and quarantines with impunity, rendering such measures useful only as an obstacle to the player. This continues into the design of the space station where the sequel is set, and protagonist Isaac Clarke gets to crawl through a few special engineer-only vents himself to get from place to place.
  • In the Rail Shooter prequel Extraction, you do get to crawl through the vents and similar locales several times, but it's lampshaded that they are tight, cramped and hard to move quickly in. The fact you only face Leapers and Crawlers in them only makes it worse.
• Deus Ex
  • The game often includes alternate paths through air vents, which usually double as maintenance tunnels, complete with ladders and hinged grates. One of the NPCs even explicitly suggests it as a stealth route in the first mission, saying that "these 20th century buildings always have ventilation shafts". However, unlike Duke Nukem, there's also always a straight way.
  • Mildly subverted in Deus Ex: Invisible War; all the vents are comfortably navigable, but inevitably are patrolled by small, spider-like security bots armed with electrical shock-based weapons. According to characters, the bots are to combat any vermin that might enter the vents.
  • And just because it was such a big part of the first game, in Deus Ex: Human Revolution, air vents abound, often leading to rooms with a couple of neat little bonuses, or an easy way around the guards. This is even lampshaded in an early conversation, where someone asks if the reason you took so long getting to his office is if you got stuck in an air duct. And not too long after, during the first mission, if you sneak in, when asked how he got in, the player character explains that he used the air-duct, and is going to include them in his presentation about security loopholes.
• Dishonored uses this trope in a quite realistic way: you can use air ducts to infiltrate buildings and, in one case, to escape captivity, but you need a special power that allows you to possess a rat to do so.
• Duke Nukem 3D did this so often that there is a small monster almost designed to be placed in the vents. In the expansion pack, the game has a nod to the famous air vent scene in the first Mission: Impossible movie.
• In Erie, these adult-man-sized ducts are the player's saving grace. The game heavily consist of sprinting away for your life from mutant monsters and luckily, they can't fit in vents.
• Escape from Butcher Bay, in which the ducts were used so widely they actually had directions scribbled inside them. Assault on Dark Athena continues this.
• The Evil Within 2 has Sebastian flee from Stefano's Gruesome Giggling Guardian by doing this, barely avoiding a Groin Attack in the process.
• An obscure 90s FPS called Expert have vents in several areas, used for taking a shortcut into adjacent rooms.
• Fashion Police Squad features air vents you have to crawl through. The vents are coated with gold.
• In The Feeble Files, Feeble has to crawl through a bunch of vents in the last sequence of the game in order to solve a number of puzzles.
• Final Fantasy:
  • Final Fantasy VII in numerous places, most notably in Shinra tower when the player eavesdrops on the evil corporate meeting from a ventilation duct connecting to a bathroom.
  • Final Fantasy VII Remake: This version of the air vent section lets you pause and eavesdrop on several offices and meeting rooms to listen in on what the Shinra office people are up to, from Reeves' subordinates making plans for repairs to one where the occupants are worried sick about their families on the recently-fallen Sector 7 plate.
• First Encounter Assault Recon requires you to travel through air ducts several times per level in order to advance deeper into the facilities you're penetrating, whose covers are quite easily bashed in. Strangely, despite the game's horror atmosphere and the obvious darkness and claustrophobia factors, you are never once subjected to any sort of scare sequence within one. Except one. During one particular part, you turn the corner, and Alma does the spider-crawl towards you — before vanishing a foot away from you. In Extraction Point, Alma pops out of an air vent right in front of you on one occasion, while you're hanging on a ladder and utterly defenseless.
• Five Nights at Freddy's:
  • Five Nights at Freddy's 2 ups the ante on the danger posed by the killer animatronics by including a pair of vents leading right to the security room, which you also have to keep an eye on. At the very least there are cameras in both vents and lights at the bits leading into your office - though why they're even big enough for the massive animatronics to crawl through is another matter entirely.
  • Continued in Five Nights at Freddy's 3, as there are two ventways into your office that Big Bad Springtrap can crawl through, but this time you are able to shut off individual vents to slow his progress. However, they tend to malfunction constantly, giving you Hallucinations if not careful.
  • In Five Nights at Freddy's: Sister Location, however, you are the one doing this instead. Nothing can actually get you in there, though the game certainly pulls no punches in suggesting something might. The secret alternate night also has vents that Ennard can crawl through, serving the same purpose with the same mechanics as in 3.
  • Freddy Fazbear's Pizzeria Simulator takes this to its logical conclusion - the entirety of the map is vents, bar your office at the back and the Pizzeria in the middle of it. It is a literal maze that animatronics can freely travel through - and there're no cameras, forcing you to use other forms of detection (specifically audio and motion tracking) to keep them away.
  • Ultimate Custom Night also contains a couple of vents for animatronics to roam around in - Springtrap returns to crawling through them, as does Ennard, and joined by a whole batch of the 50-plus characters, each with their own mechanics.
  • Five Nights at Freddy's: Security Breach: Due to being a child, Gregory is small enough to crawl through the larger air vents throughout the PizzaPlex. This proves essential for getting around several of the locked doors and evading the animatronics. But don't get too comfortable though, Wind-up Music Man Toys can spawn inside the air ducts to kill Gregory if you don't get out of them quickly enough. In the Ruin DLC, Cassie is likewise young and small enough to use the vents to get around the now-derelict Pizza Plex. Not only does she also have to deal with the occasional Music Man chase, but the vents end up collapsing under her weight at a couple of points.
• In Fran Bow Fran uses one to escape from the psychiatrist's office after Phil locks her in. Since she's a child, it's semi-plausible.
• Frosty Nights: One of the Snowlems, Yellow, will attempt to enter your room through the vents.
• Used in a level in Geist; Raimi possesses a dog to get through the vents. It appears to be a boxer-type dog, and can't stand up in the vent.
• Dharma Tower from Ghostrunner has huge air vents which the Ghostrunner has to fight his way through. They exist to filter radioactive air from outside for the people in Dharma Tower to breathe, but in-game, they mainly serve to let you slide down them to build up speed and launch towards enemies on the opposite side.
• Vent corridors appears in several stages in Gemini: Heroes Reborn, but they're usually bolted shut and you need to use your telepathy to rip the shutters open.
• GoldenEye (1997) begins the second level with James Bond infiltrating a Russian base via the air vents and winding up in the bathroom, in a Shout-Out to the opening scene from the movie the game was based on.
• In Golden Sun: The Lost Age, Felix and gang sneak into the Great Gabomba Statue, a clockwork statue worshipped as a god by a stereotypical Sub-Saharan African-like tribe, through the ventilation shaft, since the original builder's entrance has been sealed with a big rock.
• Goose Goose Duck: Ducks can travel through vents on the sci-fi maps to travel around the map or circumvent doors they have closed. In the Victorian themed maps, Goosechapel has the same mechanic using sewers instead of air vents, while Mallard Manor doesn't have vents but instead has stationary hiding places that can be used. This ability is not limited only to Ducks, however. The Mechanic, or Snoop for Mallard Manor, is a Goose role that can also use vents and hiding places.
• Half-Life:
  • Some of the first Half-Life's vents have ladders in them, suggesting that they may have been designed to allow people to go through them, and considering how deep the Black Mesa facility stretches, perhaps it is not quite unrealistic that it would use people-sized vents. One notable setpiece involves a group of soldiers noticing Gordon crawling in the vent shaft above them and opening fire, causing the vent to break apart beneath his feet.
  • Half-Life 2: Episode One mentions that Gordon used to race against Barney to break into Dr. Kleiner's office when he locked his keys inside, which is how the two of them learned to use vent shafts to their advantage. And subverted in the same game, where one vent you crawl through collapses, landing in a room filled with Exploding Barrels and laser-tripwire mines.
• Harthorn: When the Player Character enters the gym to reach the north wing of the school, he's forced to climb up to the vents and walk through them. He comes out in a washroom.
• You spend most of Heavenly Bodies' penultimate level crawling through tiny air ducts and ventilation shafts to get to the engine at the center of the space station. Unlike most examples, the lack of lighting in these vents is a problem, since bringing a flashlight will take up enough space to make navigation difficult and otherwise you can't see.
• Both played straight and subverted, for unsettling effect, in Heavy Rain, where Ethan Mars is guided by a serial killer through series of Se7en-style trials. One of them involves deliberately crawling into something that resembles both a system of wide air ducts and a dangerous exhausts vent (it sounds stupid, but looks appropriately menacing). The vent system is one foot high and branching, it's absolutely dark and hard to breathe there, and its floor is covered with broken glass.
• Hitman: Vents are all over the place in Absolution. 47 will automatically take out his lighter and hold it in front of the camera. In Silent Assassin, he can use the hospital vents to scope out which O.R. the cult leader is staying in, but the game engine wasn't ready for this yet, so the "vent" is accessible by ladder.
• Horizon Forbidden West: Played straight, and very handy for exploring ancient bunkers and other ruins.
• The online game Infantry has a "Bug Hunt" map, allowing players to play as humans or aliens, the aliens granted the advantage of traveling by air ducts and launching ambushes from them.
• Jonathan Kane: The Protector have Jennifer using an air vent to escape from terrorists during her Damsel out of Distress moment. She manages to reach a maintenance room using said vent and obtain her first weapon, a taser, from a closet.
• In Jurassic Park: The Game, Jess uses one to access the geothermal generator in the third episode, much to Gerry's anger. The Troodon use them to get around the facility, and try to break in to the room containing the heroes by using vents.
• In Just More Doors, one of the secret rooms consists entirely of such a passageway. It's Played for Laughs.
• Shows up in Kingdom Hearts III, of all places, when the heroes visit the world of Toy Story. As they're all transformed into Living Toys, the vents have plenty of room for them and the Heartless they're fighting.
• Valve hangs a lampshade on this trope in Left 4 Dead 2 with the ever-epic lines of Ellis; In Dark Carnival, he says "if there's one thing video games have taught me, it's that good shit comes from crawlin' through vents". Though unlike in Half-Life, the vents in the level he utters the line in do not lead to anything more important than an alternate route. On the other hand, some custom campaigns make them the mandatory route.
• The Legend of Heroes: Trails:
  • Trails from Zero: Some of the ducts in the Geofront are large enough for grown adults to walk through. Definitely not true for air vents in the surrounding buildings buildings though.
  • Used extensively in Trails of Cold Steel II and III where the party has to go through the vents to proceed through the levels. Various levels of enthusiasm vary with at least one character commenting on using these.
• A cutscene near the beginning of Live A Live's sci-fi chapter shows the crew of Cogito Ergosum inspecting an airduct which predictably the Robot Buddy protagonist uses in the climax to evade the behemoth on the loose.
• Mass Effect
  • While Shepard never has to enter a vent in Mass Effect 2, there are a few instances or references of vent use in the game.
    • Thane Krios uses one during his recruitment mission. You can actually hear a clunk while he's in there before he makes his big entrance.
    • During the suicide mission, the chosen Tech Expert has to move through a duct, while the player has to fight off the Collectors in order to open the valves for them. That instance should probably count as a subversion, in that the game makes very clear how very dangerous it is, and that the tech expert would have died, hideously, were it not for Shepard's help. At some points you can see them and the ducts are actually tall enough to let them walk through.
    • Most disturbingly, during Thane's Loyalty mission, Captain Bailey mentions Duct Rats, homeless children who travel in the Citadel's ventilation system. Played straight, as some of the vents can lead to razor sharp fans, sheer drops, protein vats, depressurized vents, or being spaced.
  • Used by Liara in Mass Effect 3 to escape from some Cerberus troopers. True to their real-life counterpart, they are extremely noisy - the player can hear the vents being banged around by Liara and the Cerberus troops clear across a large parking garage. While the vents are very large, the troopers have trouble getting around in their bulky armor; they repeatedly try to shoot her, but aren't able to aim and just further ventilate the shaft. There's a little boy on Earth in a smaller vent at ground level. The sound of him moving around in there is actually the only reason Shepard detects him.
  • During the Citadel DLC, temporary ally Maya Brooks has to crawl through the vent of a casino to disable the door to the panic room, all the while avoiding alarms until Shepard disables them.
• Max Payne 3 subverts this when Max scrambles into an air duct just big enough to fit him to escape a room full of tear gas. After awkwardly maneuvering himself along for a few moments, he finds out the hard way that just cause it fits him doesn't mean it can support him...
  Max: I was trying to work out what direction I was headed in when I discovered some more Brazilian architecture not designed for the "American physique".
• The Jim Dandy from MDK2 has a few air-vents that the protagonists can comfortably walk through without even needing to crouch. They are also wide enough that two people could walk abreast.
• Occurs at least once in most of the Medal of Honor games, such as the last level of Mission 2 in Allied Assault.
• Messiah has vents big enough for Bob (who is the size of a baby) to crawl through. There are also smaller vents, which you can explore while you're possessing the body of a rat.
• Frequent in the Metal Gear series.
  • In Metal Gear 2: Solid Snake, said vents are occasionally guarded by the memetically infamous Poisonous Zanzibar Hamsters.
  • One of the first areas in Metal Gear Solid has an otherwise level air duct with a lowered section in it. Said lowered section is flooded, which would render the duct useless for ventilation. Perhaps justified given the Shadow Moses base shows many signs of poor maintenance.
  • Very blatant in Portable Ops, which opens up with Snake escaping from a prison by crawling through the air vents.
• Apparently, design standards in the Metroid universe include a provision that all facilities and spacecraft must have access tunnels, air shafts, or other openings big enough for Samus Aran's Morph Ball form. (Expanded and partially subverted in Zero Mission, wherein after losing her armor, Samus must negotiate said tunnels on her hands and knees, which is dead slow, and Space Pirates can also use the tunnels, largely negating their escape value.) More accurately, it seems all maintenance robots (which use the tunnels) are the same size as the Morph Ball.
  • There's a prevailing theory (with some canon evidence) that nearly all modern technology is based on that of the Chozo unless stated otherwise and most races are too afraid to tinker with the design fundamentals unless their whole project blows up. Naturally, the Chozo would have no problem making their vent shafts just the right size for their Powered Armor warriors to take a shortcut through.
• Midnight Puppeteer: You have to travel through air vents to get to some inaccessible rooms.
• Mirror's Edge features a number of extremely large (and life-saving) air vents. Lampshaded in one instance when Faith does this and a guard can be heard below exclaiming "Wow, the rats must be huge in here!"
• Monaco, being largely an homage to heist films, features air vents as a very convenient way to get around each floor unnoticed, assuming they go where you need them to. Hilariously, not only will nobody hear you as you walk through them, but if an NPC decides to enter one, they can pass directly through you without so much as raising any suspicion. If you play as The Cleaner, you'll even knock them out as they pass by.
• In the Myst universe we have a justified version of the mine example: D'ni is an underground city, and its Great Shaft is a huge air exchange shaft. But it's also used as the primary method of reaching the surface (or vice versa).
• Pajama Sam 4 has the titular character doing this at the end of the game, even though it simply leads to the ceiling of the same room.
• The Penumbra games have these from time to time within the series. The first game has a few in the mine's storage cells, and from the textures, they actually look pretty dusty. In the second, Philip has to take the screws off a vent's cover to go in; apparently one of the scientists, Niel Oswald, had gone that way as well and left notes and red marks for someone to follow. And near the end of the second game, a third is hidden behind a rather out-of-place landscape painting. At one point, Philip also mentions that the air smells rotten even though the air circulation is on.
• A series of maintenance tunnels in The Perils of Akumos prove to be this. A separate series of air vents also prove plot-relevant.
• In The Persistence, there are lots of ground-level air vents just small enough for Zimri to crouch through throughout your perilous journey. The grates even have retinal scanners that let you open them effortlessly, and most of them have some money in them!
• In Persona 5, sneaking through air vents is sometimes the only way to advance from one area of a palace to another. While most are big enough for a human to crawl through, some of the later ones are too small— but luckily, there's a nearby statue that can turn the party into mice small enough to make use of them.
• In Phantasmat 7: Reign of Shadows the main character has to answer riddles in order to properly navigate the air ducts leading to Dr. Corvine's private section of the Arcadia Resort.
• When you're in the Team Rocket Hideout in Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, you need to get a key to use a lift, but the Team Rocket Grunt throws it on top of a wall. So how do you get to it? You send your starter Pokémon into action - and part of the route sends it through an air vent.
• You have to crawl through a series of vents to get through Dr. Hare's factory in Poptropicas 24 Carrot Island level.
• Portal 2:
  • A variant on this: At one point, Chell uses the ductwork of old Aperture to apply conversion gel in otherwise unreachable locations. She also uses access shafts and tunnels at some points.
  • The Perpetual Testing DLC features a clip of an Alternate Universe Cave Johnson warning people not to try this inside his space prison.
    Cave: Attention, test prisoners attempting to escape through the air ducts. I don't know what nonsense you learned on TV, but in real life, air ducts just go to the air conditioning unit. It's also pretty dusty, so if you've got asthma chances are you're gonna die up there. And we'll be smelling it for weeks, because, again, the air ducts aren't a secret escape hatch; they're how we ventilate the facility.
• The second Propagation requires you to enter vents to navigate around the zombie-infested rooms of a Hell Hotel. Most of these vents are bolted by default though, requiring you to obtain a powered screwdriver to proceed.
• In Ratchet & Clank (2002) you never actually climb inside the vents, although Clank would certainly be small enough to have one of his missions in there, but at one point you break into a building by climbing on the outside of external air vents with Magnet Boots.
• Rayman 2: The Great Escape: This is how Rayman escapes the pirates' prison ship. Considering that was an air vent, which is never really explained. Judging by its size, it's more likely to be where the smaller warships are sent from, if not from the deck.
• The demon in Reincarnation: Riley's Out Again does this to get around the school without being spotted by humans, but it's so "tedious and unfun" that later versions added an option to skip the sequence altogether. He's seen doing it again in a mini later in the series.
  • Also used in In the Name of Evil, but thankfully without the maze.
• Played straight in Resistance: Fall of Man when Parker uses a vent that pops open to escape from the conversion center, leaving Hale to find his own way out.
• Phil does this to escape his room at the beginning of Riddle School 5. He's a child, so the size issue isn't relevant.
• Used against the player in SCP – Containment Breach. SCP-173 uses these to get around the entire facility, and most of its spawn points are signified by a broken vent in the room.
• Secret of Evermore had an escape through the ventilation system take up a dungeon. Fortunately, to make up for the confusion of navigating the vents, the game followed the trope pretty well by having no enemies inside them.
• Sharpshooter 3D has more than one area where you crouch to enter knee-high vents, to infiltrate or exit buildings.
• Shadow Complex: A fairly prominent method of slipping through the complex, both to avoid combat and just to get around. Some of the vents are reinforced with plating that renders them resistant to everything short of a missile launcher.
• Shadows of Doubt gives this option to players for moving around buildings, though not without issues. A lack of maps for the air ducts means a player may not be able to find their exact intended location, or may even jump out into someone else’s apartment, incurring said resident’s wrath. The metal is also very cold, and someone can very easily find themselves passing out in the vents, leading to a trespassing fine on top of the hospital bill.
• The titular character of the Sly Cooper series can do this in all his games. He usually does to break into places.
• Sniper: Path of Vengeance have you escaping the prison in the first stage using the ventilation shaft. Which a nearby prisoner, uninterested to escape, will helpfully point out for you.
• Sonic Adventure: The game actually makes use of this a number of times in order to progress from level to level. For example, Sonic and Tails travel through the vents of Casinopolis in order to find the Chaos Emerald located there.
• Spider-Man:
  • In Spider-Man (2000), Spider-Man has to escape from an underwater base using the air ducts... which are big enough for him to web-swing through.
  • In Spider-Man (PS4), this is frequently used by Peter to circumvent locked doors and silently take out enemies. Spidey even lampshades it early on, remarking how clean the vents are in Fisk Tower.
• Sam Fisher of Splinter Cell has an odd ability to encounter ridiculously large vents with grates off to get into areas that would otherwise be unreachable. Somehow, a guy carrying a large gun as well as a few pounds worth of other weapons and gadgets doesn't make enough sound to alert anyone. There's a particularly bizarre instance in the first game where Sam makes his way into a walk-in freezer. Given that the vent in question is connected to a regular part of the building, it means the vent is just wasting coolant.
• SPY Fox starts with this in the third game, Operation Ozone, infiltrating an enemy base through the restroom's ceiling vent.
• In episode one of Strong Bad's Cool Game for Attractive People, Strong Bad must use the air vent to sneak past The Poopsmith while infiltrating the King of Town's castle. However, unlike some other examples here, you can get caught if you aren't careful.
• Justified in Styx: Master of Shadows. Styx, being a goblin significantly smaller than a human, can crawl through many ventilation shafts and pipes that are way too small for a human. Although this may sound like a security oversight, when the Atrium was built, there was no such thing in existence as a goblin.
• In Subnautica, you can occasionally find aquatic ventilation shafts built by unknown aliens for an unknown purpose. Most creatures avoid them, but tiny Peeper fish can and do swim in and out with ease. The captive, colossal Sea Emperor has been telepathically directing the Peepers to do so. Her/Its Enzyme 42 is the only cure for the local plague, so she's using the Peepers to distribute it.
• Super Mario Bros.:
  • Super Mario Sunshine: These are on top of the third floor of the Hotel Sirena, which is mainly needed to find a way into locked rooms.
  • Paper Mario: The Thousand-Year Door has Mario go through air ducts twice in the course of plot in order to eavesdrop. He may also go through a third in order to gain an item.
• Syndrome has air vents that you can use to sneak around the ship.
• System Shock has whole maintenance tunnels in addition to vents, and System Shock 2 almost starts with one.
• Team Fortress 2: Most of the air vents are inaccessible and just for decoration, but there are a few in Hydro that are big enough for players (even the Heavy Weapons Guy) to stand up in. Custom-map-made-official Turbine has a system of these that's more of a cramped hallway than a vent. One sadistic mapmaker made a version of Turbine where the vents are literally a maze leading from one spawn to the other.
• The Escapists features these. The vents are protected by vent covers, requiring you to break them open or unscrew them. The Escapists 2 also has these, except for the fact that they now span multiple floors and take less effort to break open.
• The Thing (2002): At one point, Blair acquires access to another room by walking hunched through a four-foot-wide air duct.
• Some stages in Tom and Jerry Chase have these, which can be used as shortcuts between rooms that are far apart.
• Vampire: The Masquerade - Bloodlines has a series of air vents (with ladders leading to them, no less) in the garage in the Downtown area. During the mission for Fat Larry that takes you there, a stealthy character can make good use of them and avoid combat entirely- a good idea, as the enemies there are heavily armed and quite numerous. Later in the game when a mafia bouncer blocks your progress, Malkavian characters can ask the bouncer if there are any vents that they can use instead.
• Warframe: Both Grineer and Corpus maps have plenty of air vents big enough for a warframe to walk through (Infested maps have them as well, but they're overgrown with Meat Moss.) Grineer maps tend to require them to progress through the level, while in Corpus maps they're usually optional for stealth.
• In Wax Worx you use one to get from Professor Wily's workshop to the Lizzie Borden exhibit.
• Werewolf: The Apocalypse — Earthblood: When in Lupus form, Cahal can crawl around in air ducts to move without being spotted and bypass locked doors.
• Wild AR Ms 1: Downplayed. Only Hanpan, the little mouse sprite belonging to one of the main characters, is small enough to navigate the air vents.
• X-COM:
  • XCOM Enemy Within: The base-defense mission has the aliens using air vents to gain access to part of the XCOM base. Justified in that the aliens coming through the air vents are either Sectoids or Thin Men; the former are very small, while the latter are incredibly flexible.
  • XCOM: Chimera Squad: This is Torque's special breaching ability, as a Viper she has the agility to pull it off. Downplayed Trope, as it is just an effective way to breach a room and bypass cover bonuses, with any hit she scores during the Breach generating a stun. The ability can be used by others agents, but they need a specific equipment piece to do it.
• XIII has this a lot. Justified in that the player tends to machine gun all the bad guys ahead of time so there's nobody left to hear him clunk clunk through the shafts.
• During Wolverine's escape from the Weapon X facility in the X-Men Origins: Wolverine game, he has to crawl through ventilation shafts a few times to avoid attention (thanks to his healing factor being temporarily disabled). In one of them, a guard down below yells about hearing something and starts riddling the shaft with bullet holes. Another guard tells him to stop being jumpy, and that it's ridiculous that Wolverine would be up there.

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