This is an organization, and we use the term loosely, that enrolls adventurers and gives them access to jobs. Jobs generally range from "find my cat" to "destroy Omega Volcano Satan", and are posted by random locals who can't, apparently, do anything for themselves. It's very likely that jobs will be ranked by difficulty, with precise but vague credentials required for more dangerous jobs.
Jobs generally are posted on a bulletin board (which may be an encrypted dataserver or a cork slab, depending on the setting), where certified adventurers sign up for them. "Certified Adventurers" is basically a euphemism for "freelance mercenaries" or, in more cynical terms, "murder hobos". The Protagonist will commonly be one because it is a convenient frame narrative for introducing side quests and plotlines. It can be used for everything from the Knight Errant to the Psycho for Hire to hidden royalty.
If Craigslist had a section labelled "Jobs wanted: Medieval Commando Squads", it would be one of these.
It is mainly a video game trope, but also shows up in anime, especially when the setting is a Role-Playing Game Verse. Mainly shows up in Japanese works, perhaps because the Japanese seem to feel that even killing people and taking their stuff should be done in a structured, social context.
A subtrope of We Help the Helpless, but there's something more specific here. It has to do with the concept of a medieval guild adapted to serve the needs of a video game.
Real-life guilds were established to safeguard their members from competition and outside economic forces and had official license from the government to be the sole tradesmen in a city; despite this, fictional guilds will often form rivalries and compete with each other in a quasi-market economy. This furthers perception of these groups being more akin to companies of mercenaries than actual "guilds".
One more thing: Although the main characters are commonly described as a guild, they usually don't have a common skill set. Fighters, mages, and thieves (and others) can all work for the same guild, but won't learn skills from each other. After all, that would make them similar, and What Measure Is a Non-Unique? (There are occasionally organizations that cater to these types, but then we get into politics.)
See also Weird Trade Union, Murder, Inc., Thieves' Guild. Compare Creature-Hunter Organization and The Order, which has a more rigid structure and better-defined purpose, and Private Military Contractors, the modern mercenary company counterpart. Also compare Hero Academy, which focuses primarily on teaching students in successfully dealing with quests like those mentioned above (especially if such quests are strictly heroic) though may have some elements of Adventure Guild.
- Avernum has a bulletin board in every town that supplies you with jobs and quests.
- In The Bard's Tale, the Adventurer's Guild building is the main headquarters for your adventurers. In between games 2 and 3, however, the Guild is destroyed along with the rest of Skara Brae.
- The protagonists of Pokémon Mystery Dungeon: Explorers are members of the Wigglytuff Guild, whose tasks range from menial chores to discovering mysterious places.
- The Guardians in Destiny function very similarly to this trope, with the Tower serving as a large base where Guardians from all across the system trade loot, acquire quests, train, and generally commiserate. This is lampshaded often, with many noting that the, uh, unique mental states of Guardians (i.e., they act like RPG characters in-universe), this trope is pretty much the only effective way to keep them organized.
- The old Eamon computer game had the Guild of Free Adventurers, the place where you always started your adventures and where you returned when you finished. It had a number of functions you could access while there. May be the Trope Maker
- The Elder Scrolls: Various Guilds and Factions are joinable in each game starting with Daggerfall. They tend to be more function-specific and function more like actual medieval guilds than the odd job clearinghouses that epitomize this trope. The Fighters Guild comes closest to the standard definition of the trope, offering tasks ranging from low-end critter killing to being Bounty Hunters to protection services to, at the high-end, dealing with supernatural threats. The Companions take this role instead in Skyrim.
- Fable I: The Heroes' Guild recruits and/or trains powerful individuals, who accept quests from various groups in Albion for fame, profit, bloodlust, or genuine honour. At various times in its history, the Guild was everything from a benevolent peacekeeping force to a cutthroat mercenary organization. Fable II reveals that, soon after gunpowder was invented, the Guild was disbanded with extreme prejudice by citizens who had gotten fed up with being at the Heroes' mercy.
- The Bracer's Guild from the Trails Series. The lore goes on to explain a bit of how they function: they're a non-government organization that's allowed to operate among the nations who agree to host them. They do follow regulations, though: while they have legal authority to perform arrests, they are not allowed to arrest politicians, and they are not allowed to break any laws of the nation they're in while carrying out contracts. Due to the fact that they operate outside of the authority of the government they're seen in a poor light by the military as well as more influential figures.
- The latter Mega Man Battle Network games have bulletin boards full of Side Quests to do. Which ones can be done is typically limited by a ranking system.
- The Trouble Center in Paper Mario: The Thousand-Year Door
- Phantasy Star had a Hunter's Guild starting from Phantasy Star IV and onward. In Phantasy Star Universe they were renamed Guardians but essentially do the same killing of monsters and handling of odd jobs. In Phantasy Star Online 2, they are rebranded as ARKS, with their duties expanded to combating Darkers and investigating planets to determine their viability for colonization.
- The Adventurer's guild in the Quest for Glory series, although they typically only granted you the low level stuff, big things had to be done by convincing people you were the one to do them.
- The protagonists of Rakenzarn Tales all eventually belong to the Nutsy Guild of Densel Town. Besides serving as a base of sorts, it's also where you can access the game's sidequests.
- Rune Factory 2 and Rune Factory 3 have a bulletin board where townspeople post quests
- In Solatorobo, the adventurers are called Hunters, but there are many guilds, the largest of which are the Kuvasz.
- The eponymous Star Wolves are a freelance starfighter squadron who make their living this way.
- Vector Thrust boasts organisations of dubious legality like Bastille and Heron, which will get mercenaries an airbase to call home and a steady stream of contracts in conflicts around the world. Most of them specialise in the lawless territories of the Kingdom
- This is the primary mechanism to get missions in Wing Commander: Privateer.
- Xenoblade Chronicles X has BLADE, the military force of New Los Angeles. BLADE, itself, is divided into eight "Divisions" which specialize in different tasks and provide their own unique benefits to their members:
- Pathfinders specialize in exploration and installing data probes. They have improved HP recovery.
- Interceptors specialize in combating indigens and completing missions. They receive a buff to ranged damage.
- Harriers are combat specialists tasked with fighting indigens and tyrants. They receive a buff to melee damage.
- Reclaimers specialize in treasure box acquisition and data probe installation. They have improved drop rates.
- Curators specialize in combating tyrants and collecting items. They have improved critical hit rates.
- Prospectors specialize in collecting resources and exploration. They receive a buff to their defenses.
- Outfitters specialize in aiding in Arms Manufacturer R&D and collecting Miranium. Their earnings from mining probes are increased.
- Mediators specialize in quest completion and aiding other BLADEs. They receive TP from using Arts in addition to normal attacks.
- Final Fantasy XIV has the Adventurers' Guild, which formed after an abrupt cessation of a war with The Empire saw massive numbers of soldiers and mercenaries suddenly out of work. To prevent these free blades from turning to banditry and the like, the Guild was formed to organize and dispatch them on quests that range from delivering mail, gathering materials for craftsmen, exploring dangerous/remote areas or killing monsters. The Guild is the main source of work for the Player Character for the first sections of the game. As the story progresses, it falls into the background as the Warrior of Light begins interacting with major political players and secret societies on their own, but the Guild always happily acknowledges that the Warrior is still one of theirs made good.
- Genshin Impact has the Adventurers Guild, an organization that can be found in every nation that supplies odd jobs for the common folks. All Adventurers' Guilds are staffed by a woman named Katheryne, who tiptoes around the question of why she's seemingly omnipresent. In-game, they're the source of various daily activities such as Commissions, Expeditions and occasionally certain timed Events.
Non-Video Game Examples
- Wizard guilds in Fairy Tail are this, rather than a Magical Society you might expect. This is because magic in this setting is informal and unique to the individual, and its practitioners are basically superpowered heroes for hire rather than Robe and Wizard Hat types.
- High Level Familia such as Loki Familia operate as this in Is It Wrong to Try to Pick Up Girls in a Dungeon?. In addition to slaying monsters in the titular dungeon they very frequently take on quests to retrieve drop items or rare materials from the dungeon, especially the lower levels, or act as escorts for members of the Familia more focused on crafting to gather the materials themselves. The Guild (which is not this, despite the name) can also issue quests directly, such as commanding Familia to participate in the defence of the city against would be invaders.
- These exist in the various cities of E-Rantel in Overlord, both taking requests for various missions to fight against the monsters of the world as well as setting prices and overseeing the ranking system that governs individual adventurers.
- The world of Goblin Slayer also has ones similar to those in Overlord. The titular Goblin Slayer is infamous in the guild for only taking quests that involve killing goblins.
- Soul Eater has a very videogame-esque job board at the school, complete with estimated number of souls the students will receive on completion of the mission.
- That Time I Got Reincarnated as a Slime: The Free Guild originally established out of the Kingdom of Ingracia (though technically it's beholden to no nation) functions likes this. In exchange for paying taxes to the various nations out of which its branches operate, they have a great deal of autonomy in how they run things and take various requests from the nations, smaller villages, or even individuals. They also have adventurer training, ranks, and tests to promote rising candidates. Notably, the guild is rather new innovation as adventurer society was much less organized and looked down on in the past before the Otherworlder (and videogame-lover) Yuuki Kagurazaka arrived and reorganized the whole system into its current incarnation as its head. The irony being that Yuuki is also the Big Bad.
- I've Been Killing Slimes for 300 Years and Maxed Out My Level: The Magical Land into which Azusa is reincarnated has an Adventurer's Guild branch in the nearby town, among other RPG-Mechanics Verse elements. Azusa sells the crystals she collects from killing slimes there, and its Stat-O-Vision artifact kicks off the main plot by revealing just how powerful she's become.
- In The Night Unfurls, this is the place where sellswords get their bounties. Judging from how Kyril has wandered from place to place to sell his blade to those who needed it, many of these exist throughout Eostia, in contrast to the usual depiction of one single guild with a Random Power Ranking in Japanese media (Kuroinu is a Japanese visual novel with an anime adaptation). Then again, mercenary work is stated to be a booming business in Eostia, so this makes sense.
- Occurs in some D&D settings:
- Adventurer's Guilds are common in Eberron. The city of Sharn has two competing ones, the Clifftop and Deathsgate guild.
- The Pathfinder Society is this trope for Pathfinder. The society is dedicated to explore Golarion, investigating ruins, recovering tomes and artifacts as well charting the world. Not confuse with Pathfinder Society, the official organized play campaign where the PCs are members of the eponymous organization.
- The Royal Pioneers of Pugmire originated as an organization for funding and equipping expeditions across the acid sea, but since Pugmire lost access to their one port on the sea it's been focused one dungeon delving a bit closer to home. The Monarchies of Mau, not to be outdone, have their own version named Trillani's Trailblazers after their first (and thus far only) single ruler.
- Black Star in Shadowrun was a militant wing of the Anarchist Black Cross that provided training and support for the titular Shadowrunners, originally Neo-Anarchist mercenaries who were paid by the Mega Corps to sabotage their competitors and inadvertantly chip away at the system they had created. However, Black Star was decimated in 4th edition during the Az-Am War, and "modern" Shadowrunners tend to be freelancers only in it for the money.
- Shadowland (and its successor Jackpoint) is a downplayed version of this trope, being a Message Board for shadowrunners. Posting is by invitation only, but reading is open to anyone who can find the place. While actual job offers are rare, the boards often have long discussions on useful info for Shadowrunners both professional and green and many famous lore characters (including several of the Great Dragons) have been known to pop in on occasion.
- The Mercenary Review Board and later the Mercenary Review and Bonding Commission in Battletech fits the trope. It brokers and arbitrates contracts between hiring parties and mercenary units, registering units to give them legitimacy (as opposed to unregistered units that are essentially Space Pirates or bandits) and POW rights and protections if their members are captured, as well as enabling units to ransom back their captured troops. Rating units on their reliability and skill, holding units responsible for fulfilling their contracts, and ensuring that only legitimate contracts were offered, the MRB and later the MRBC operated as more than just a clearinghouse for jobs.
- Adventurers Guild, unsurprisingly.
- The Mercenary Guild in Daughter of the Lilies seems to lean in this direction, given some of the unconventional assignments it hands out.
- Monsters Can Be Heroes Too starts with the world's cutest little monster walking into the Adventurer's Guild asking to join up.
- Kirby Adventure has Kirby forming one of these, the Kirby Adventure Squad.
- An alternative to Dungeon Crawling in Latchkey Kingdom for professional adventurers. Quests are posted on the board in the morning, and range from gaining 20 Bear Asses to finding a lost cat to fighting a Titan. Hilla has a lot of adventurers, so the quests tend to run out immediately, causing a minor kind of Retail Riot.
- Pokemon Mystery Dungeon Gleaming Hearts has the Guild of Flowers based in the village of Fleur, and Team Gleam's first official mission from them is to carry a message to the Drybone Guild in the desert.
- Slightly Damned has something very similar called the Trouble Center, though the jobs that they give out don't involve killing monsters, and are mostly helping people with random stuff.
- Widdershins: The titular magic-rich Adventure Town has the Royal Society of Hunters to take bounties on dangerous artefacts, Magic Misfires, and rogue wizards. The Gentleman Adventurer Henry Barber was one of its most famous members, and his granddaughter follows in his footsteps in the time of the comic.