History Main / EmptyRoomUntilTheTrap

*** The MiniBoss room of the third dungeon, [[WombLevel Inside Jabu-Jabu's Belly]], has a large platform that is inaccessible to you, but to [[EscortMission Princess Ruto]] when you toss her onto it. You have to do so so she can get the third Spiritual Stone, the Zora's Sapphire, which she had been looking for after Jabu-Jabu swallowed her, and eventually becomes yours so you can open the Door of Time in the Temple of Time after the boss of that particular dungeon has been defeated [[spoiler:(though not before [[AndNowYouMustMarryMe she holds you to the promise of marrying her]])]]. After Ruto takes the Sapphire, the platform rises up to the top of the room, taking her with it. Ruto vanishes, as a result, and you're left to deal with a Bigocto. Moreover, that platform has spikes on its sides, which spin in the opposite direction Bigocto is running in during the fight, but it eventually becomes a one-way elevator to the hallway up above where Ruto was taken to after you win.

*** The MiniBoss room of the third dungeon, [[WombLevel Inside Jabu-Jabu's Belly]], has a large platform that is inaccessible to you, but to [[EscortMission Princess Ruto]] when you toss her onto it. You have to do so so she can get the third Spiritual Stone, the Zora's Sapphire, which she had been looking for after Jabu-Jabu swallowed her, and eventually becomes yours so you can open the Door of Time in the Temple of Time after the boss of that particular dungeon has been defeated [[spoiler:(though not before [[AndNowYouMustMarryMe she holds you to the promise of marrying her]])]]. After Ruto takes the Sapphire, the platform rises up to the top of the room, taking her with it. Ruto vanishes, as a result, and you're left to deal with a Bigocto. Moreover, that platform has spikes on its sides, which spin in the opposite direction Bigocto is running in during the fight, but the platform eventually becomes a one-way elevator to the hallway up above where Ruto was taken to after you win.

*** The MiniBoss room of the third dungeon, [[WombLevel Inside Jabu-Jabu's Belly]], has a large platform that is inaccessible to you, but to [[EscortMission Princess Ruto]] when you toss her onto it. You have to do so so she can get the third Spiritual Stone, the Zora's Sapphire, which she had been looking for after Jabu-Jabu swallowed her, and eventually becomes yours so you can open the Door of Time in the Temple of Time after the boss of that particular dungeon has been defeated [[spoiler:(though not before [[AndNowYouMustMarryMe she holds you to the promise of marrying her]])]]. After Ruto takes the Sapphire, the platform rises up to the top of the room, taking her with it. Ruto vanishes, as a result, and you're left to deal with a Bigocto!

*** The MiniBoss room of the third dungeon, [[WombLevel Inside Jabu-Jabu's Belly]], has a large platform that is inaccessible to you, but to [[EscortMission Princess Ruto]] when you toss her onto it. You have to do so so she can get the third Spiritual Stone, the Zora's Sapphire, which she had been looking for after Jabu-Jabu swallowed her, and eventually becomes yours so you can open the Door of Time in the Temple of Time after the boss has been defeated [[spoiler:(though not before she holds you to the promise of [[AndNowYouMustMarryMe marrying her]])]]. After Ruto takes the Sapphire, the platform rises up to the top of the room, taking her with it. Ruto vanishes, as a result, and you're left to deal with a Bigocto!

*** In the first dungeon, you have to look up and find the boss on the ceiling.

*** The MiniBoss room in Arbiter's Grounds has a large sword embedded in the center of the room, but when you cut one of the ropes holding it onto the floor, it burns away the other ropes and an apparition appears wielding it, which can be seen in wolf form until you make it partially solid enough to attack it as a human.

*** The miniboss in the Snowpeak Ruins is in what looks like a simple hallway with two suits of armor on display. Then when you get to the other end of the hallway both doors suddenly lock and the [[HeWasRightThereAllAlong suit of armor immediately behind you]] is smashed by the other one, which comes to life wielding a [[EpicFlail ball and chain]], which eventually becomes yours after you've defeated it.

*** In the Forest Temple, the boss room is empty. Realizing this, you leave. This triggers the boss battle.

*** The mini-boss in the Snowpeak Ruins is in what looks like a simple hallway with two suits of armor on display. Then when you get to the other end of the hallway both doors suddenly lock and the suit of armor immediately behind you is smashed by the other one, which comes to life wielding a ball and chain.

* ''VideoGame/MonkeyIsland2LeChucksRevenge'' has the seemingly empty guest room in the Woodtick Hotel. If you wait in here a while without going behind the dressing curtain Largo [=LaGrande=] will come in here and shout at you for coming in his room, and then kick you out.
** And then later on, ''you'' set a trap for ''him'', in the very same room!
** Even later, you have to come in there with the VoodooDoll and shock him. After this the room is really empty.
** These scenes are echoed in the last act of the game. You are in an underground building where you have to search several empty rooms to gather various items to build a VoodooDoll of [=LeChuck=]. However, at any given point, [=LeChuck=] can enter the room and electrocute you. You therefore have to build the VoodooDoll and be able to immediately use it on him when he walks in.

* ''{{VideoGame/Doom 3}}'' was notorious because of this to the point it didn't shock or surprise the player. They just knew as soon as they entered the empty room and touched the item they'd immediately have to turn around and blast all the monsters that teleported into the room.
** The Doom games before it reveled in this as well. First rule of Doom: Everything is a trap. ''EVERYTHING''. Even the ''exit rooms''.

*** Another variant of this is used later on, where there is a large, seemingly empty room in a factory filled with snipers, however the snipers won't spawn until the player is close enough, preventing the player from clearing out the room from a distance.

* In ''VideoGame/ShinMegamiTenseiIV'', one of the shelters in Kasumigaseki has a room that can only be accessed by having at least 100 Luck. Open the room and you find absolutely nothing...unless the RNG decides to fall on the 1/256 chance of [[BonusBoss Red Rider]] appearing in that room, though you will be given a chance to leave if you aren't up to the task.

** In ''VideoGame/TheLegendOfZeldaSkywardSword'', one level requires visiting three mini-dungeons to find the next main one. The final room of the second initially looks like an empty room with some sand, but after some dusting Moldarach (the final boss of the Lanayru Mining Facility) inexplicably shows up for a rematch.

!!Video Game Examples:

** And they actually did it in module ''[[spoiler: X2 Castle Amber]].''

** In ''VideoGame/TheLegendOfZeldaALinkToThePast,'' the dungeon beneath the Village of Outcasts has a room like this. The compass tells you that it is the boss's room, but there is no boss... until you bomb its ceiling and lead a certain prisoner into the light...

*** In the first dungeon, the boss room is empty until you think to look up and find the boss on the ceiling.

Compare HeWasRightThereAllAlong, EmptyRoomPsych (which this trope often leads to), SuddenlyHarmfulHarmlessObject, TeleportingKeycardSquad, DropInNemesis (where the trap results in instant death), and WallMaster.

** In ''VideoGame/TheLegendOfZeldaALinkToThePast,'' the dungeon beneath the Village of Outcasts has a room like this. The compass tells you that it is the boss's room, but there is no boss... until you bomb its ceiling and lead a certain prisoner into the light...

** In the first dungeon of ''VideoGame/TheLegendOfZeldaOcarinaOfTime'', the boss room is empty until you think to look up and find the boss on the ceiling.

*** Halfway through the Water Temple, you come into an infinite, foggy wasteland filled with ankle deep water and a small island with a dead tree in the center. There's nothing particularly interesting about the room, and when you reach the other side, you find that the exit door is barred shut, and your reflection is gone. Only then will you find that one of the most fun/confusing fights of the game has been waiting, watching you from that tree.
*** It's interesting to note that if you walk backwards to the door, Dark Link will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, Dark Link will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

*** It's interesting to note that if you walk backwards to the door, Dark Link will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, Dark Link will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

Compare HeWasRightThereAllAlong, EmptyRoomPsych (which this trope often leads to), SuddenlyHarmfulHarmlessObject, TeleportingKeycardSquad, DropInNemesis (where the trap results in instant death).

*** It's interesting to note that if you walk backwards to the door, Dark Link will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, Dark Link will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

[[folder:Video Games]]
* ''VideoGame/{{Abuse}}'' has a nasty habit of putting players in that appear empty, but as soon as they flip a switch or advance further in the area and--'''WHAM!''' A horde of mutants show up and starts ganging up on them.
* ''VideoGame/BioShock1'' had a few of these. Examine a certain item placed in the corner of a room, and when you turn around -- surprise! There's a splicer right behind you that wasn't there a second ago! "Hello, beautiful!"
* ''{{VideoGame/Doom 3}}'' was notorious because of this to the point it didn't shock or surprise the player. They just knew as soon as they entered the empty room and touched the item they'd immediately have to turn around and blast all the monsters that teleported into the room.
** The Doom games before it reveled in this as well. First rule of Doom: Everything is a trap. ''EVERYTHING''. Even the ''exit rooms''.
* In ''VideoGame/Fallout4'', the VeryDefinitelyFinalDungeon of the ''Automatron'' DLC has a long hallway lined with apparently empty jail cells. However, if you hit the circuit breaker on the wall, which happens to be inconveniently placed next to an elevator switch, a dozen [[DemonicSpiders high-level Feral Ghouls]] emerge from the cells.
* ''Franchise/FinalFantasy'':
** ''VideoGame/FinalFantasyII'' has many empty rooms with very high encounter rates. It drops you off in the middle, and you'll probably have to fight a battle or two on your way out.
** ''VideoGame/FinalFantasyIV''
*** The infamous "closing wall" room (just before the throne room) in the Baron Castle, which has no significance until you try to walk back through it after you beat Cagnazzo, and requires the [[spoiler:death of two of your party members in order to proceed]].
*** The bridge in [[ThatOneLevel the Sealed Cavern]]. You walk across a bridge and get the Dark Crystal of Earth, then walk back onto the bridge, where you're confronted by [[TimeLimitBoss the Demon Wall]].
%%* The catacomb pitfalls in ''VideoGame/KingsQuestVI''.
* Parodied in ''VideoGame/KingdomOfLoathing'''s Daily Dungeon. The protagonist recognizes the trap rooms instantly (and with some weariness), and can either trigger them (which does enormous damage but removes the obstacle)) or set them off at a distance with an item.
* ''VideoGame/Left4Dead'' has these in the form of crescendo events. In most levels, there will be a room that will have a few zombies, but won't spawn any more into the map until the survivors press a button or something that alerts a horde to their location.

* ''Franchise/MassEffect'':
** The first encounter with the rachni on Noveria in ''VideoGame/MassEffect1'' includes at least one rachni soldier popping out of a vent as Shepard leaves the room.
** ''VideoGame/MassEffect2'' has both the Collector ship from the standard game and the geth ship from the ''Overlord'' DLC, which have upgrades, money and the like dotted around, but either the enemies are inert, or they're not visible at all. In both cases, you reach a well-defined midpoint, and then everything goes to hell in moments.
* Many side rooms in the ''VideoGame/MedalOfHonor'' series only serve [[TeleportingKeycardSquad to trigger ambushes]].
** In ''VideoGame/MedalOfHonorVanguard'' as soon as the player walks into the empty lounge in the Chateau after clearing it out, a Panzer 4 will blow a hole in the wall and [[{{Teleporting Keycard Squad}} several other tanks supported by infantry will spawn around the Chataeu]].
*** Another variant of this is used later on, where there is a large, seemingly empty room in a factory filled with snipers, however the snipers won't spawn until the player is close enough, preventing the player from clearing out the room from a distance.

* ''Franchise/{{Pokemon}}'':
** The "Monster Houses" in the ''VideoGame/PokemonMysteryDungeon'' series, which appear empty until 30 or so enemies drop from the sky the moment you set foot in them.
*** Unless you scan for items, since such trap rooms tend to have abundance of loot.
*** Also at the beginning of secret episode 4 in ''Explorers of Sky'' (Here Comes Team Charm), a Graveler walks into a room with a treasure chest and statues of Lopunny, Gardevoir and Medicham, long story short the statues come to life and take the treasure for themselves, (info can be found [[http://bulbapedia.bulbagarden.net/wiki/Here_Comes_Team_Charm! here]]).
*** Such "Monster Houses" are common in [[RogueLike Pokemon Mystery Dungeon's genre]], but they are usually filled beforehand.
** In ''VideoGame/PokemonDiamondAndPearl'', there are a couple of occasions like this. The first is the ghosts in the Old Chateau which will appear out of nowhere even if the rooms look empty. The second is a small room in Stark Mountain, where the room seems empty until you leave and go back in, at which point Heatran has appeared from nowhere.
* Boss rooms in ''VideoGame/QuakeII'' and ''VideoGame/QuakeIV'' tend to be empty of enemies until the boss suddenly teleports in. This is usually triggered by the completion of an objective, such as shutting down the security grid in ''II'', or the Tetranode in ''IV''.
* ''VideoGame/ResidentEvil1'' has the room with Plant 42, the attic, the inaccessible room upstairs in the mansion, that when you get the key and go in its empty until you examine the piano, then Giant Mutant Snake. Its first strike at the player breaks a hole in the floor that gives you access to the basement, which is only accessible after the boss fight.
** There's also the infamous tiny, nondescript room you pass through before finding a shotgun [[SchmuckBait innocently hung on the wall]]. Unless you like Jill Sandwiches, you'd better have a replacement for that shotgun or Barry to save your butt.

* All over the damn place in ''VideoGame/SeriousSam'' games. You'll frequently encounter places that are empty except for [[SuspiciousVideogameGenerosity a powerup or two.]] Go far enough into the area, or pick up the powerups, and mooks start teleporting in en masse.
* In ''VideoGame/ShinMegamiTenseiIV'', one of the shelters in Kasumigaseki has a room that can only be accessed by having at least 100 Luck. Open the room and you find absolutely nothing...unless the RNG decides to fall on the 1/256 chance of [[BonusBoss Red Rider]] appearing in that room, though you will be given a chance to leave if you aren't up to the task.
--> '''[[MissionControl Burroughs]]:''' "[[JumpScare I'm detecting a]] [[BossWarningSiren very dangerous demon nearby.]] [[ThisIsGonnaSuck You should consider]] [[ScrewThisImOuttaHere getting out of here]]."
* The bathroom in ''VideoGame/SilentHill3''.
** Later on, the "bloody mirror room" in the alternate hospital.
** Take the dagger out of the fridge in ''VideoGame/SilentHill1'' without first locking the door with the Ring of Contract, [[NonstandardGameOver and an unknown monster comes out of the fridge and eats you]].
* ''VideoGame/TalesOfSymphonia'' uses this to remove characters from your party just before the ([[DiscOneFinalBoss apparent]]) endgame; there are six rooms that the heroes pass through, and in each one is a trap of some sort that requires one party member to stay behind to hold open a door, hold off enemies, etc.
* ''Trapped 5'' has the first two boss rooms marked only by a preceding hallway with a question mark on the floor that says "Beware" if you examine it. You enter the room and the door locks behind you. Once you go up to the other door, then the boss appears.

!!Examples From Other Media

[[folder:Film -- Live-Action]]
* Virtually every room in ''Film/{{Cube}}''. Two characters are killed by a RazorFloss wire trap, and one is killed by giant speakers that pulverize his body with sound waves. FridgeLogic dictates that they should have been able to see the NoodleImplements that should've killed them, but they don't. The characters soon catch on to this, and start throwing boots and other objects into empty rooms before going in.

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons'' has a monster that pretends to be a ceiling, and a monster that pretends to be the floor, monsters that cover the walls ''and'' almost invisible jelly monsters in the size of a usual Empty Room. Combine them all to create the infamous Room of Death, which appears empty until all of it tries to eat you.
** And they actually did it in module ''[[spoiler: X2 Castle Amber]].''
** Put the monster that looks like a treasure chest in the middle and the monster that looks like a door on the far wall, and you've got the Room of Vile Death. Put a pool of the monster that looks like water in the corner, and you get stuck with the whole pizza bill for the night.
** And of course there's not a DM alive who has never used the ParanoiaFuel aspects of this trope to get their players worked up over a ''genuinely'' empty room. It's fun to watch them poke every square inch of a 10x10 room with a stick, swing their swords in a panic at casually mentioned details like some moss in the corner, and maybe even waste spells trying to divine the room's purpose or buff themselves up for a fight that never happens.

*** It's interesting to note that if you walk backwards to the door, the boss will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, the boss will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

** In ''VideoGame/TheLegendOfZeldaSkywardSword'', one level requires visiting three mini-dungeons to find to next main one. The final room of the second initially looks like an empty room with some sand, but after some dusting Moldarach (the final boss of the Lanayru Mining Facility) inexplicably shows up for a rematch.

!!Examples:

[[folder:Film -- Live-Action]]
* Virtually every room in ''Film/{{Cube}}''. Two characters are killed by a RazorFloss wire trap, and one is killed by giant speakers that pulverize his body with sound waves. FridgeLogic dictates that they should have been able to see the NoodleImplements that should've killed them, but they don't. The characters soon catch on to this, and start throwing boots and other objects into empty rooms before going in.
[[/folder]]

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons'' has a monster that pretends to be a ceiling, and a monster that pretends to be the floor, monsters that cover the walls ''and'' almost invisible jelly monsters in the size of a usual Empty Room. Combine them all to create the infamous Room of Death, which appears empty until all of it tries to eat you.
** And they actually did it in module ''[[spoiler: X2 Castle Amber]].''
** Put the monster that looks like a treasure chest in the middle and the monster that looks like a door on the far wall, and you've got the Room of Vile Death. Put a pool of the monster that looks like water in the corner, and you get stuck with the whole pizza bill for the night.
** And of course there's not a DM alive who has never used the ParanoiaFuel aspects of this trope to get their players worked up over a ''genuinely'' empty room. It's fun to watch them poke every square inch of a 10x10 room with a stick, swing their swords in a panic at casually mentioned details like some moss in the corner, and maybe even waste spells trying to divine the room's purpose or buff themselves up for a fight that never happens.
[[/folder]]

* The bathroom in ''VideoGame/SilentHill3''.
** Later on, the "bloody mirror room" in the alternate hospital.
** Take the dagger out of the fridge in ''VideoGame/SilentHill1'' without first locking the door with the Ring of Contract, [[NonstandardGameOver and an unknown monster comes out of the fridge and eats you]].
* The "Monster Houses" in the ''VideoGame/PokemonMysteryDungeon'' series, which appear empty until 30 or so enemies drop from the sky the moment you set foot in them.
** Unless you scan for items, since such trap rooms tend to have abundance of loot.
** Also at the beginning of secret episode 4 in ''Explorers of Sky'' (Here Comes Team Charm), a Graveler walks into a room with a treasure chest and statues of Lopunny, Gardevoir and Medicham, long story short the statues come to life and take the treasure for themselves, (info can be found [[http://bulbapedia.bulbagarden.net/wiki/Here_Comes_Team_Charm! here]]).
** Such "Monster Houses" are common in [[RogueLike Pokemon Mystery Dungeon's genre]], but they are usually filled beforehand.
* In ''VideoGame/PokemonDiamondAndPearl'', there are a couple of occasions like this. The first is the ghosts in the Old Chateau which will appear out of nowhere even if the rooms look empty. The second is a small room in Stark Mountain, where the room seems empty until you leave and go back in, at which point Heatran has appeared from nowhere.

* Boss rooms in ''VideoGame/QuakeII'' and ''VideoGame/QuakeIV'' tend to be empty of enemies until the boss suddenly teleports in. This is usually triggered by the completion of an objective, such as shutting down the security grid in ''II'', or the Tetranode in ''IV''.
* ''VideoGame/TalesOfSymphonia'' uses this to remove characters from your party just before the ([[DiscOneFinalBoss apparent]]) endgame; there are six rooms that the heroes pass through, and in each one is a trap of some sort that requires one party member to stay behind to hold open a door, hold off enemies, etc.

* In ''VideoGame/MedalOfHonorVanguard'' as soon as the player walks into the empty lounge in the Chateau after clearing it out, a Panzer 4 will blow a hole in the wall and [[{{Teleporting Keycard Squad}} several other tanks supported by infantry will spawn around the Chataeu]].
** Another variant of this is used later on, where there is a large, seemingly empty room in a factory filled with snipers, however the snipers won't spawn until the player is close enough, preventing the player from clearing out the room from a distance.
* ''VideoGame/FinalFantasyII'' has many empty rooms with very high encounter rates. It drops you off in the middle, and you'll probably have to fight a battle or two on your way out.
* ''VideoGame/FinalFantasyIV''
** The infamous "closing wall" room (just before the throne room) in the Baron Castle, which has no significance until you try to walk back through it after you beat Cagnazzo, and requires the [[spoiler:death of two of your party members in order to proceed]].
** The bridge in [[ThatOneLevel the Sealed Cavern]]. You walk across a bridge and get the Dark Crystal of Earth, then walk back onto the bridge, where you're confronted by [[TimeLimitBoss the Demon Wall]].

* ''Trapped 5'' has the first two boss rooms marked only by a preceding hallway with a question mark on the floor that says "Beware" if you examine it. You enter the room and the door locks behind you. Once you go up to the other door, then the boss appears.

* ''VideoGame/BioShock1'' had a few of these. Examine a certain item placed in the corner of a room, and when you turn around -- surprise! There's a splicer right behind you that wasn't there a second ago! "Hello, beautiful!"
* ''VideoGame/ResidentEvil'' has the room with Plant 42, the attic, the inaccessible room upstairs in the mansion, that when you get the key and go in its empty until you examine the piano, then Giant Mutant Snake. Its first strike at the player breaks a hole in the floor that gives you access to the basement, which is only accessible after the boss fight.
** There's also the infamous tiny, nondescript room you pass through before finding a shotgun [[SchmuckBait innocently hung on the wall]]. Unless you like Jill Sandwiches, you'd better have a replacement for that shotgun or Barry to save your butt.
* The first encounter with the rachni on Noveria in ''VideoGame/MassEffect1'' includes at least one rachni soldier popping out of a vent as Shepard leaves the room.
** ''VideoGame/MassEffect2'' has both the Collector ship from the standard game and the geth ship from the ''Overlord'' DLC, which have upgrades, money and the like dotted around, but either the enemies are inert, or they're not visible at all. In both cases, you reach a well-defined midpoint, and then everything goes to hell in moments.
* Inverted in ''VideoGame/RobotOdyssey'' which forces you to do a puzzle to get a token each time you need to ride the subway. Because of this, players are hesitant to get off at Jack-in-the-bot station because there are no doors in the room. They appear and open only when you get off the subway.
* ''VideoGame/{{Abuse}}'' has a nasty habit of putting players in that appear empty, but as soon as they flip a switch or advance further in the area and--'''WHAM!''' A horde of mutants show up and starts ganging up on them.

* Parodied in ''VideoGame/KingdomOfLoathing'''s Daily Dungeon. The protagonist recognizes the trap rooms instantly (and with some weariness), and can either trigger them (which does enormous damage but removes the obstacle)) or set them off at a distance with an item.
* In ''VideoGame/Fallout4'', the VeryDefinitelyFinalDungeon of the ''Automatron'' DLC has a long hallway lined with apparently empty jail cells. However, if you hit the circuit breaker on the wall, which happens to be inconveniently placed next to an elevator switch, a dozen [[DemonicSpiders high-level Feral Ghouls]] emerge from the cells.

* The catacomb pitfalls in ''VideoGame/KingsQuestVI''.

*** It's interesting to note that if you walk backwards to the door, the boss will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, the boss will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

** One room in the Lakebed Temple appears to be empty at first and Midna advises you to look around. Then you realize that small tadpole-like enemies are dropping down from the ceiling, and you look up to see the dungeon's mini-boss, a giant toad, who drops down to fight you.
** The mini-boss in the Snowpeak Ruins is in what looks like a simple hallway with two suits of armor on display. Then when you get to the other end of the hallway both doors suddenly lock and the suit of armor immediately behind you is smashed by the other one, which comes to life wielding a ball and chain.

*** It's interesting to note that if you walk backwards to the door, the boss will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, the boss will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

** In ''VideoGame/TheLegendOfZeldaTwilightPrincess'', one room in the Lakebed Temple appears to be empty at first and Midna advises you to look around. Then you realize that small tadpole-like enemies are dropping down from the ceiling, and you look up to see the dungeon's mini-boss, a giant toad, who drops down to fight you.

[[folder: Film ]]

[[folder: Tabletop Games ]]

[[folder: Video Games ]]

* In the first dungeon of ''VideoGame/TheLegendOfZeldaOcarinaOfTime'', the boss room is empty until you think to look up and find the boss on the ceiling.
** In the Forest Temple, the boss room is empty. Realizing this, you leave. This triggers the boss battle.
** In the Fire Temple, you can actually leave the boss room, provided you have not jumped out onto the battle platform yet.
** Halfway through the Water Temple, you come into an infinite, foggy wasteland filled with ankle deep water and a small island with a dead tree in the center. There's nothing particularly interesting about the room, and when you reach the other side, you find that the exit door is barred shut, and your reflection is gone. Only then will you find that one of the most fun/confusing fights of the game has been waiting, watching you from that tree.
*** It's interesting to note that if you walk backwards to the door, the boss will not appear. He will only appear if you turn the camera around so he can't be seen when he appears. When you turn around again, the boss will be standing by the tree, just waiting.
*** Even moreso than that, he only appears if you walk over the island in the center, at which point your reflection disappears from beneath you when you step upon the water again.

** In ''VideoGame/TheLegendOfZeldaTwilightPrincess'', the one room in the Lakebed Temple appears to be empty at first. Then you realize that small tadpole-like enemies are dropping down from the ceiling, and you look up to see their mother, a giant toad, who drops down to fight you.

* In ''VideoGame/PokemonDiamondAndPearl'', there are a couple of occasions like this. The first is the ghosts in the Old Chateau which will appear out of nowhere even if the rooms look empty. The second is a small room in a cave, where the room seems empty until you leave and go back in, at which point Heatran has appeared from nowhere.