Developer's Room

"Congratulations! You found me! Here, have some points."

— Christy Marx, Conquests of the Longbow

The Developer's Room is an area in a video game filled with Author Avatars and in-jokes. It has no bearing on the story, it's just an Easter Egg — but that doesn't make it any less fun, as it may also contain some additional rewards and goodies for the player alongside all the "thank you for playing our game" messages. Unlike a Debug Room, which almost always requires a code (sometimes a built-in one, sometimes not), a Developer's Room can often be reached on a normal playthrough.

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Examples:

Action Adventure

• Bloody Spell, a Chinese-made wuxia game, has one of these... in the Ming Dynasty. You take a detour in some caverns, hack apart a flimsy wooden wall in a secret area, and uncover a room filled with laptops, programming software, soda machines and posters promoting the game. As the game was developed in 2020, there are even notices on the wall reminding employees to "wear a facemask at all times".
• Eternal Daughter has one. You can't actually enter the room; your character can only sit quietly in the secret passage on one side, watching the game's two developers as one works on the code and the other works on graphics of the main character herself.
  "Hey, I just got a great idea for Eternal Daughter 2..."
  "...shut up, shut up, shut up!"
• Hollow Knight has the Shrine of Believers, which contains tablets with messages from each of the Kickstarter backers, and is accessed by using the Dream Nail on the tall moth statue in the Cave Behind the Falls in the Spirits' Glade.
• La-Mulana has three developer rooms, one for each of the game's three developers. You need a special ROM combination to be able to listen to them.
• Related: The Chris Houlihan room in The Legend of Zelda: A Link to the Past, which can only be reached if the game fails to load an area. Chris Houlihan was actually the winner of a Nintendo Power contest which meant his name would appear in a game. Apparently, this was how the developers decided to do it (the room exists in other regional versions of the game, but Chris Houlihan's name is only in the American version).
• LEGO Island 2: The Brickster's Revenge (for the PC) had a room hidden in the cave on the side of a mountain that, with the proper typed code and 100% game completion, contained LEGO avatars of a good deal of the design and production team for the game.
• Mercenary The Second City had a series of triangular doors in different locations in the game. These doors would normally require a triangular key but this did not appear in the game, and the manual stated "only the author has it". There was, in fact, an easter egg which would allow these doors to be opened, giving access to a developer's room: a massive hall with the endpoint of every triangle door in the game (allowing you to teleport quickly around the game, and to escape from prisons that would normally have no exit) and a bar of gold that could be sold for enough money to buy anything in the game.
• After the credits roll in Mission Impossible for the N64, the character is returned to the embassy level from the beginning of the game, except this time, the party goers are replaced by the game's developers.
• Prince of Persia: The Sands of Time had a developer's room in the remake of Prince of Persia, in place of the exit to the first level. The room was full of discarded snack boxes and had a giant mural of the game's staff on the far wall.
• Star Control 2 was going to have one of these as the Secret of the Rainbow Worlds, but they ended up not doing it since they couldn't come up with enough gags for it.

Action Game

• Custom Robo had one after beating the entire game in the apartment next door of the protagonist's room.
• Gauntlet: Dark Legacy had a secret stage taking place in the offices of Midway, and had a lot of in-jokes although the developers themselves never appeared (although a few of their faces did).
• Ambrosia Software rents office space in Harry the Handsome Executive's setting, ScumCo Tower. The staff is out when you visit, but they each left you a memo.
• The PS1 version of Xena: Warrior Princess has a developer's room in the underground maze level, right before the Minotaur boss battle. While turning left leads to the Minotaur, turning right leads to a dead end with a single burning torch, and if you walk towards the dead end, you'll find out that you can walk right through the wall, into the developer's office.
• Zombies Ate My Neighbors finishes on one of these. After defeating Dr Tongue, you go to a bonus level, "The Monsters Among Us," set in the LucasArts office and featuring Author Avatars.

Action RPG

• In Deus Ex: Invisible War, when you get to the snowed-over UNATCO base, if you flush the toilet in Manderley's office, then you'll access a secret dance party, complete with floating data cubes containing quotes from the development of the game and characters from all over the game saying odd things. Make sure you save your game before you enter, though! The only way out of the dance party is to reload your last save.
  • This was also a Shout-Out to the original game where fiddling with the flag in Manderley's office early on in the game unlocked a special dance party ending cutscene.
• Diablo III has two.
  • The base game's Cemetery Of The Forsaken usually has three of the four passages open, leading to Defiled Crypts, one of which you need for story progression. Occasionally the fourth will also be open, in which case it leads to an area literally called Development Hell, where all the enemies are named after the dev team members and given Boss Subtitles according to their jobs; killing its Final Boss, Jay Wilson - Game Director, offers an achievement.
  • The Reaper Of Souls expansion moves the devteam into a rare Nephalem Rift. Jay had quit Blizzard by then, so the Rift Guardian is instead Josh Mosqueira - Reaper Of 'Soles. Again there's an achievement for killing him ("Mosquito Swatter").
• Dungeon Siege II has a secret dungeon that has high level groundhogs and copies of your party members that you must defeat in order to reach the developers room.
• Fallout 2 has one as a random encounter on the world map.
  • Fallout 3 has an area called the Bethesda Ruins, which actually is an upscale suburb (Bethesda, Maryland) in the Washington, DC metro area. And yes, that's where Bethesda Softworks was founded in real life (they since relocated north to Rockville, Maryland, which although is also in the DC area, is completely absent from the game).
    • The designers prided themselves on how geographically accurate the map of DC is. After all, they do live there.
  • If you hold shift while clicking on the credits option on the main menu, both Fallout and Fallout 2 will instead show you a series of quotes and messages from the developers and playtesters.
  • The Fallout 2 Restoration Mod features a special encounter on the world map that can only be seen after beating the game, featuring everyone who worked on the mod as Star Wars characters.
• Final Fantasy IV: It's hidden in the Dwarves' castle. It was removed from the English-language SNES release (probably due to the maps being removed to make room for the expanded training room and because the secret Porno Mag item would not get past Nintendo's strict censors at the time.), then restored in later versions and in the Namingway Edition hack of the US SNES version. Note that the characters found in the DS version are different, to reflect the development team for that version specifically.
  • The location is also accessible in After Years as well, but the place is empty and there's a note on the door that says "Old Developer's Room, new location will be posted later". A later chapter changes the sign to read "Please do not look for us". The new location is on the moon, found by using a warp to go to "???" after a major story event and then using a secret passage.
• The original Star Ocean on SNES also has one, which is accessible by using the otherwise useless Oracle skill after beating the game: strangely enough, doing so is also the only way to leave the final dungeon and visit the Bonus Dungeon located elsewhere, which doesn't become accessible until you beat the game.
• In Terranigma, a minor sidequest in Neotokio unlocks the Quintet offices.
• Titan Quest features one such room per expansion pack. Each requires the player to find a hidden key to unlock the door to it, and within are enemies named after the developers, as well as a chest filled with exclusive, Easter Egg Lethal Joke Equipment.
• In the 1989 game Vampyr: Talisman of Invocation, the gods of the world that the player meets in Heaven after dying are the programmers of the game. They judge the player based on his actions, and presumably allow him to be reincarnated. It's also possible to fight them, but they're bloody tough. Killing one particular eunuch jester in Heaven gains the player a whole load of experience points and the favour of the gods.

Adventure Game

• Adventure, likely the Ur-Example, had the famous Easter Egg room where the developer signed his name with the walls. (When it was made, Atari had a policy of not including programmer credits).
• Even early works with no NPCs to speak of, such as Scott Adams's Adventureland, include rooms like "I'm in the memory RAM of an IBM PC. I took a wrong turn!"
• In Beyond Zork, you can travel to the dimension of the Implementors (development team) and have lunch with them.
• Chicory: A Colorful Tale: If the player completes every single Collection Sidequest and explores the entire world map, the dev team's avatars appear at Pizza's house to talk about making the game.
• The granddaddy of all adventure games, Colossal Cave, features something like this. When you have solved all the puzzles, you are transported to a backstage area full of game props and snoozing dwarves, and have to make your way to the exit.
  • In a variant, the earlier Infocom game Enchanter allowed you to summon the Implementors.
• As listed in the opening quote, Conquests of the Longbow. The developers vacillate over how many points to give you, finally deciding on zero.
• Else Heart Break has at least three.
• King's Quest IV: The Perils of Rosella. If you go to a certain room (in certain versions of the game) and enter the text command "Beam Me", you end up in a starship in orbit, staffed by sprite versions of the people at Sierra who made the game.
• In one of the Leisure Suit Larry games, the people in the Disco are named after the devs.
  • In Leisure Suit Larry 3: Passionate Patti in Pursuit of the Pulsating Pectorals, the player can find developers Al Lowe and Ken Williams in several places: When first approaching the two at a club, the player can say a short phrase to the two, after which Al and Ken discuss the idea of putting themselves in the game and having Larry say something to them, only to conclude that it's way too implausible and teleport away.
• The VGA remake of Quest for Glory I turns Baron von Spielberg's throne room into this at the end of the game, with members of the dev team making cameos amongst the normal characters.
• Logic gate-programming game Robot Odyssey: Escape from Robotropolis had one that was fairly easy to access that gave you a suitcase and a keyhole that didn't do anything.
  • The Java fan remake, Droidquest, used this room as part of the method for accessing the secret sixth level of puzzles.
• The Stanley Parable: One of the endings in the HD Remake leads to the player discovering a museum full of trivia about the development of the game.
• The old 1980s text game Video Game/Transylvania had a hidden chamber full of the company's mascot penguins wearing sunglasses who would deliver an advertisement for one of the company's other games. The PC then wakes up outside the room again, feeling disoriented.
• Epiphany City has a dev room hidden underneath a large building in the third major area, the park.

Driving Game

• During the credits of Driver, Tanner drives through Newcastle-upon-Tyne, the hometown of Reflections. This was originally meant to be a playable area, but got Dummied Out, although there is a mod for the PC version that allows access to it.
• Rush 2: Extreme Racing USA has a entire course set in Midway's offices.
• Vette! has the island suburb of Alameda, which is where Spectrum Holobyte was headquartered.

First-Person Shooter

• Blood (1997) has the Monolith office as a Blood Bath level, most noticeable for featuring the cut Beast monster which Caleb would have originally been able to transform into.
• Chex Quest has a secret dimly-lit room with photos of the development team on all the walls.
• The first Dark Forces game features a hidden room in the fourth level. It's unusual as a trope example because you explicitly need a code to get there (the one that toggles height check, so you can fall any distance without dying and climb any cliff just by bumping into it). You get to shoot an ewok.
• Doom II: The final level in the game contains a hidden room with John Romero's head in it. In fact, the Romero head is the actual final boss - the big demon you shoot at is just a wall texture.
• Duke Nukem 3D has a developer's level, inaccessible in normal gameplay that contains the developers as dead astronaut wall textures. They can also be seen with Duke in the ending of the third episode.
• Halo: Reach's ninth level has the "Tribute Room", which contains various Bungie- and Halo-related easter eggs, including seven Marathon-style terminals thanking parts of the fan community. Interestingly, the room is actually revealed in a cutscene to be Dr. Halsey's lab; the aforementioned terminals are even written from her perspective.
• Each of the Marathon games has a "developer's terminal" hidden in its final stage.
• Painkiller: Battle Out Of Hell has a secret level featuring portraits of the developers scattered around a castle, and the goal is to collect all their souls and leave. This level is only accessible by beating Battle Out Of Hell on Trauma difficulty, which in itself is only accessible by collecting at least 9 out of the 10 possible Black Tarot cards and beating the game on Nightmare difficulty.
• Postal 2 has you visit the developers' offices on the very first level, complete with author avatars, only to learn that you've been fired and the offices are being stormed by protestors. The developers can all be killed with no effect on the game. This was a response to criticism of the previous Postal game, and in particular to one protestor asking the lead developer "How would you like being shot?"; clearly within a game, he wouldn't mind at all.
• Shoot a broken wall after beating the last boss in Quake II and you'll find a room with gigantic pics of the developers. Activate them for extra fun, then drop down a hole to find a relaxing Tank surrounded by rotting cyborg hotties.
• Serious Sam includes a room in the first level which is filled with giant-headed versions of all the Croteam developers.

MMO

• City of Heroes had one... well, two, both more specific to the artists than the devs in general. The original was in City Of Villains, in the highest level zone, with a "No Players Allowed" sign in front. This place got trashed, and the new Developer's Room was in one of the newer City Of Heroes zones. It wasn't closed off as such, just pretty well-hidden. The first lasted for some time before a player found it, and the second was discovered in days (or maybe hours) after the zone was introduced.
• Final Fantasy XIV also had one for the 2015 Rising Event, which was the second anniversary of A Realm Reborn's launch. In the event, the Wandering Minstrel (who was an Author Avatar that has been in the game for a while) is investigating an issue that turns out to be Lampshade Hanging on bots and debugs. After completing it, he brings you to the developer's room, which turns out to be filled with wacky AuthorAvatars for several of the developers. Interestingly, due to this game in the series being an MMORPG and events only being temporary, the Developer's Room was temporary as well, and it remains to be seen if we'll ever get to go there again.
• The developers of Temtem, Crema, have an in-game office building in Neoedo. They make allusions to the game's development, and there's a sidequest where you do menial tasks for them.
• World of Warcraft has the "Developers Playground", where many objects and NPCs are strewn about randomly as they were being tested out. There are also many 90 degree cliffs, broken patches of terrain, and spots where the third person camera that usually follows the player stops moving as you run away. While it's inaccessible to players on live servers, earlier versions of the game had some tricks that allowed access to similar development areas. One area, the Caverns of Time, was accessible by normal players months before it was added in the next expansion pack, in a semi-unfinished state.
• zOMG! has one of these, consisting of a tavern in the First Town.

Platformer

• In episode 2 of Bio Menace, there's one level that seems to be nothing but a long chamber with a villain-gloat cutscene in the middle. But some tricky jumping can reveal a special key and land the player at a secret door (helpfully labelled "Secret Door") containing three developers, one of whom complains to another about leaving the door key where the hero could get it. The room has some handy powerups and various (unusable) items from other Apogee games. If you shoot the developers, one pulls out a rapid-fire version of the game's strongest player weapon and proceeds to mow you down unless you get out quick.
• Celeste: In Chapter 6, there exists a hidden developer room that can be accessed by going in the opening above Granny, and then completing the room through the use of advanced techniques that are taught later in the game.
• In Drawn to Life, if you donate enough coins to the Raposa Village's wishing well, you will be taken to the "Developer's Grove," which is filled with developer avatars. While most of them have silly things to say, one of them notoriously trolls the player with an Urban Legend of Zelda about saving the Mayor's life, which isn't actually possible to do.
• In the Cave Story Fan Sequel Jenka's Nightmare, at any point in the game where you could Sequence Break with some effort, instead of going to the next logical map, you'll be sent to a "Secret Room". Inside this secret room is the modding author, ZarroTsu, seen to be working on the game while in the game. Accessing all five Secret Rooms and walking through Jenka's fireplace takes you to the Super Secret Room containing a Boss Rush.
• The Ratchet & Clank series has the Insomniac Museum, which can be accessed in Going Commando (by getting all Skill Points and Weapon Mods, by using a hidden teleporter on Boldan between 3 AM and 4 AM [It's developed by Insomniac Games after all], or by jumping off the grind rail at a certain point, going over to the building containing the teleporter, finding a non-solid wall to go under the building and jumping through the floor), Up Your Arsenal (by getting all 15 trophies or using a hidden teleporter on Kerwan between 3 AM and 4 AM again) and A Crack in Time (by rescuing all Zoni, beating the game, and defeating Optional Boss Lord Vorselon for the third time). As its name implies, it also doubles as a behind-the-scenes gallery of things scrapped during development of the games.
  • Ratchet & Clank (2016) also contains the Insomniac Museum, but it's different from the aforementioned three. Instead of containing things that didn't make it into the game, it just contains things from every game from the first through that game (although none of it can be taken, only looked at) and the movie scenes that appeared in the game, plus two of the Japanese commercials for Going Commando.
  • Ratchet & Clank: Size Matters and Secret Agent Clank also have the High Impact Games treehouse, which also contains the gallery.
• The ROM hack Super Mario World 2+3: The Essence Star has one in the final level where, during the Pop Quiz, if you give the wrong answer to the final question, you will see a scene where the author has to deal with people demanding him to pay for the use of their graphics.

Puzzle Game

• Antichamber has several, all of them hidden behind some of the game's most challenging puzzles.
• The PC version of Chip's Challenge contains a secret level called "Thanks to..." in which the developers' names are spelled in the tiles, and a "hint" block thanks the testing team.
• Patrick's Parabox: One of the worlds unlocked post-game is a gallery that shows graphics from past iterations of the game, with a few levels playable in the graphical style of one of these builds.
• In the Portal 2 Game Mod Portal Stories: Mel, the office area where you find Virgil at the beginning of Chapter 3 has three offices with pictures of the developers in them.
• In Scribblenauts, one of the teleporter's six destinations is one of these.
• In The Talos Principle, also by Croteam, there's a secret area that can be accessed from the first lobby by walking through a non-solid wall, which contains robots like the one you're playing as, except they have monitor heads with the developer faces on them.
• Wandersong has one, though it isn't recognizable at first. At the beginning of the game, there is an area by the Bard's house that is occupied by a cat. The cat will tell you to come back later. When you return at the very end of the game, inputting a randomized password based on the symbols of the Overseers will allow you to enter a room occupied by three people who worked on the game.

Role-Playing Game

• Barony: The Hall of Trials has a gate at the far end that the player cannot open. Through an elaborate series of secrets found around the level, you can open the gates and get into the Master's Wing, where chests contain every item and spell in the game. A lever here will conjure a random monster to fight.
• In BoxxyQuest: The Gathering Storm, finishing the main story unlocks Intersite Town, an entire developers’ town with plenty to see, including a Sound Test, a “Rarity Showcase” that explains all of the game’s hidden items, a house where you can rewatch the credits, and a huge museum filled with tons of behind-the-scenes trivia. If you have a swimsuit, then you can also trigger a Beach Episode while you’re here.
• Completing Brave Soul at least once will unlock the Staff Room. This place has the best weapon shop in game, and the person you need to talk to for unlocking the Bonus Dungeon.
• Chrono Cross has a developer's room similar to the one in Trigger described below accessed in a similar manner.
• Chrono Trigger: The "best" ending, achieved by beating Lavos at the very first opportunity,^note There are two possible first opportunities depending on whether you're on New Game Plus or not, and both lead to the same ending sends you to an entire developer's building, with enough developer-avatars to fill a dozen rooms.
• Divine Divinity has a secret area which developers are in, and needs to be rescued. One of them will grant you game's secret armor after you destroy all the bugs (as in, game bugs).
• Dragon Age: Origins has the graveyard in Haven, which is filled with tombstones containing quips and jokes from the dev team, such as "Here Lies Multiplayer." The graveyard can only be accessed by leaving Haven after completing the Gauntlet, then returning later. Since there is no plot-related reason to go back to Haven once you've acquired the Sacred Ashes of Andraste, it's extremely easy to miss this particular Easter Egg.
• Not an actual room that can be explored, but in EarthBound (1994) checking a sign in Fourside reveals the message "Planning Meeting for EarthBound 2."
  • Mother 3 itself has what is more of a Developer's Hotel Room. This can't be explored either, but you can listen to the dialogue of the people inside.
• The Elder Scrolls III: Morrowind has a few which cross over with Debug Room. In particular is the ToddTest cell, which contains NPCs with such dignified names as Todd's Super Tester Guy and Pretty Kitty. The area contains one of nearly every type of item in the game.
• Endless Frontier EXCEED has one that's accessible after beating the Superboss, it's where you get a piece of Bragging Rights Reward equipment, and if you feel like beating the entire Bonus Dungeon multiple times, you can get extra copies of it by revisiting the dev room which you can carry over to New Game Plus.
• July Anarchy: Prologue, a Neverwinter Nights Game Mod, is meant to be played with a precreated character included in the game files. Trying to play the mod without playing as him sticks the player in a cross-shaped room whose floor, walls, and ceiling are covered in lava like a cheap symbolic Hell. The room is occupied by special NPCs representing characters that were deleted from the current version of the mod, with a description explaining their in-development history and why they don't appear in the mod.
• Machina of the Planet Tree -Planet Ruler-: After beating the game, the player will be allowed to save, which loads into the sound test room. Talking to the Author Avatar several times reveals plans for an update to the game and a sequel.
• Might and Magic 6, 7 and 8 each featured a dungeon called NWC full of civilians with the names of New World Computing (the games' developer) employees. Might and Magic 6 even has Jon Van Caneghem (CEO of NWC) and Trip Hawkins (CEO of 3DO, who owned NWC at the time) represented as hostile goblins that attacked your party.
• Nocturne: Rebirth has a dev room that can be accessed if the player beats the Final Boss with all party members at or below level 35. Unlike most examples, this one contains several Optional Bosses of varying difficulties, including a Hopeless Boss Fight.
• Every mainline Pokémon has either a branch office where the player can meet the game's staff or a hotel room where you can talk to a designer who's on vacation. Going to this location after completing the Pokédex will get you a 100% Completion certificate from them.
  • This is also how you unlock the GB Sounds key item in HeartGold and SoulSilver.
  • From Pokémon Black and White onwards, you're able to battle Shigeki Morimoto once a day, with Morimoto being a designer and programmer who has been involved in the series from the beginning. He's best known for personally designing Mew and adding it to the game at the last minute, a move credited for making Pokémon a Cash-Cow Franchise.
  • You can also battle another developer, Koji Nishino, in Black 2 and White 2. His team includes a Snorlax, based on an in-joke concerning Nishino's tendency to eat moldy food from the company fridge.
  • In Sun and Moon, winning against Morimoto the first time grants you an item that speeds up egg hatching. Showing him certain Pokémon that originated from the Virtual Console releases of Red and Blue to him will have him reveal some tidbits about Red and Blue's development ^note specifically, Mankey, Tauros, Exeggutor, Diglett and Mew.. Ultra Sun and Ultra Moon throws in Gold and Silver development facts and a set of Apricorn Balls if you show off creatures from the VC releases of those games, in addition to a double battle against Kazumasa Iwao (the game's director, who happens to have a unique character model).
• Radiant Arc: The Mysterious House is where the developers' in-game avatars are headquartered. This place includes various artworks and several bonus bosses, including the lead developer, Danny.
• SaGa Frontier: Can only be accessed after completing all the characters' stories. You can re-battle bosses from other stories with the character you most recently cleared with, and there are some stronger versions of bosses to be fought there as well.
  • The English patch for Romancing Saga 3 by Mana_Sword also added one into the game, accessible via an overelaborate sidequest bordering on Urban Legend of Zelda in execution (kill a specific major boss with a specific party member present, kick him out of the party, listen to the song he sings afterwards, take the new item that has somehow appeared in your storage, go bug a random NPC until he takes it and tells you to go pray for a miracle, get another specific party member in your party, get to the end of a semi-obscure dungeon that now has a new option in the dialogue box that pops up at the end). It uses Shinon, a town normally inaccessible beyond the introductory cutscene as its base and unlike most other examples given here, it does give you several pieces of Game-Breaker equipment, including a powered-up form of a weapon that's only normally usable in battle temporarily, a powerful spear that's normally only gotten as a random drop from a powerful boss and a stupidly powerful piece of armor that normally comes pre-equipped on a certain character, can't be removed once equipped (not that you'd want to) and you only normally get vastly inferior fake versions of it during normal gameplay.
  • Another SNES fan translation that followed the Romancing Saga 3 example is Cyber Knight.
• Freeware game Standstill Girl has one in the form of Alice's Backyard. You can unlock it with a password; it gives some details about the True Ending and about the game development.
• The Tiamat Sacrament: The reward for obtaining all the Soul Gems and beating the True Final Boss is access to the newly rebuilt throne room, where the NPCs will explain the development of the game, as well as hint towards a hidden tenth Rune Blade. Unusually for most examples of this trope, the room contains both dev NPCs and story NPCs, with the latter continuing to remark on plot relevant events as if they were in a normal gameplay session rather than a dev room.
• Undertale has a dev room behind a locked door that can only be opened by avoiding all the Special Thanks in the True Ending credits. Inside, it is revealed that the Annoying Dog programmed the entire game by barking into a computer with speech-to-text software.

Simulation Game

• FreeSpace 2:
  • A cheat code will cause a pirate ship to warp in (that's right, a pirate ship. In a space combat game) with the developers' faces on the pirates.
  • And it is the single toughest ship in the game, with ten billion hitpoints... several orders of magnitude more than a Sathanas juggernaut!
• Goat Simulator
  • One map features a house that turns out to be the workplace of Coffee Stain Studios, the game's creators, depicted as being hard at work on a Flappy Bird ripoff.
  • The Goatz map features one house filled with desks and computers, and in the living room is a man crying while the television displays negative reviews for the game.

Survival Horror

• Misao has one that can be accessed by entering a special code after reaching the "Truth" ending. This allows the player to see some prototype artwork and learn details about the characters only revealed inside.

Third-Person Shooter

• Max Payne:
  • The first game has two: One hidden room where you get a radio message from the developers, and one where a TV plays a short Star Trek parody with the characters voiced by the developers.
  • The second game had a memorial for a developer who died during production.

Visual Novel

• Completing Utawarerumono nets you this as well as Battle Data, a sort of bonus achievements set. The devs try and kill you for some reason or another. You'll also find To Heart and Comic Party references.

Wide Open Sandbox

• Escape Velocity Nova includes a star system hidden in the middle of dead space after completing a major story-line, which holds ships designed to be avatars of dev team members who are also found randomly in the game.
• Even Garry's Mod uses this trope: there is a secret room in the default map (gm_construct) that can be accessed via noclip and contains a "thank you" message from the mapper.
• In Saints Row IV, there is a hidden room in Let's Pretend that contains cut-outs of the development team's faces, as well as a secret weapon that is otherwise unobtainable: the Loud Locust.

Other

• Microsoft Excel of all programs had one: the surprisingly creepy Hall of Tortured Souls in Excel 95.
• The Final Fantasy IV fanfic Smut! is about a character exploring of these rooms. Because he lives in a setting where computers haven't been invented yet, he is very confused and creeped out by what he finds.
  He could scarcely believe the insanity before his eyes. They called this place the '1991 Dev Team Office.' That 1990 other locations existed or once had in this world with such a structure seemed impossible, yet that provided the only logical conclusion. Ordinary people slaved over desks in very different attire from each other. (...) A couple men slept soundly on beds, one mumbling gibberish about movies and bugs.

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