Only Smart People May Pass

"He has figured out Monsieur Adell's greatest weakness: His inability to think."

— Tink, Disgaea 2: Cursed Memories

This refers to any barrier that requires the heroes to solve some kind of puzzle, Riddle or test of skill in order to pass. It is often given by Threshold Guardians (especially if the guardian in question is a Riddling Sphinx). You must be able to work it out based on the clues you are given on the spot.

It's often a defense against smart people who want to take whatever is being guarded like a Treasure Room. It can also be a Secret Handshake of sorts to only allow smart people inside like Mensa.

If you must come to it with some knowledge, it's Only the Knowledgable May Pass. Sometimes if those who tried to deploy that trope were clumsy, they gave you enough clues to make it this, and conversely, if the answer to this is too weird or insane, you may really need to know it in advance.

The architect must have deemed this a better barrier than, say, a lock and key carried on someone's person instead of being in a chest elsewhere in the building. After all, keys can be stolen but knowledge is intangible. Unfortunately, this will not stop people who are evil in addition to smart or at least smart enough to trick the heroes into solving the puzzle for them.

See Block Puzzle, the various Stock Puzzles and Stock Video Game Puzzles, Riddle Me This, the Knights and Knaves puzzle and Solve the Soup Cans for examples of this. Note that the puzzle itself is often not terribly difficult; after all, the viewers have to be able to follow it (or solve it themselves, in a videogame). This often leads to Fridge Logic about why it wasn't solved earlier or what the point of such a simple puzzle really was. Expect even the least smart of protagonists to be able to find a way to solve what was supposed to be an ingenious puzzle.

This trope dates back to at least the Sphinx in Greek Mythology, making it Older Than Feudalism.

Compare Only the Worthy May Pass and These Questions Three...; see also see First-Contact Math; and contrast Only Idiots May Pass. Subverted in Doom as Test Prize, where one of these turns out to be a way to dispose of people who are a bit too clever. As mentioned above, Riddling Sphinx is particular form of this. Life-or-Death Question may overlap with this, although in those cases, it's more like only the smart survive.

---

Examples:

Anime & Manga

• Subverted in Azumanga Daioh when Tomo is asking complicated puzzles requiring lateral thinking. Class genius Chiyo is stumped by them, but class space cadet Osaka answers them all without any hesitation.
• Beelzebub: A demon sets up a magical quiz show for the main characters. Since they're all complete morons, this horrifies them far more than the world-ending threats they had been facing up to that point.
  Demon: So what you need to do is—oh, he died before I finished my explanation.
• In a completely justified example, the entrance exam in Detective School Q (Detective Academy Q) is filled with this sort of thing.
• In Dragon Ball Super, Vegeta suggests to Beerus and Champa that only those fighters who can pass through a simple intelligence test are allowed to participate in the tournament between Universe 7 and Universe 6. For some reason, he completely ignores the fact that he has Idiot Hero Goku and Fat Idiot Buu in his team, effectively eliminating Buu from the tournament and almost eliminating Goku in the process, while all members of Champa's team pass through the test (although Magetta has trouble during the test), giving Beerus's team a disadvantage in numbers.
• One of the pre-Hunter Exam trials in Hunter × Hunter asks you who you'd choose to save, your mother or your lover. When Gon notices the first guy (who chose the mother) was sent to his death, he realizes no answer is right, and says nothing. Again, no answer is right. They pass.
• The lower levels of Mahora Academy's Library Island in Negima! Magister Negi Magi is filled with these, as Negi and the Baka Rangers found out the hard way in an early chapter. However, these were deliberately placed by the headmaster, who appears to have plotted the whole adventure to force the Baka Rangers to study for their finals. The characters treat it more like Alphabet Soup Cans.
• Ojamajo Doremi has Doremi answer a somewhat-Sphinx inspired riddle. "Thin in the day, thick in the night, it disappears when it sleeps." Answer: Cat's eyes.
• Subverted in Princess Tutu. After a mysterious spirit kidnaps Mytho, Ahiru races to find him—and is asked riddles along the way. Ahiru, being an Idiot Hero, gets them all wrong, but it turns out that the voice wasn't testing her, but telling her who it was—a lamp.
• In Summer Wars, Kenji solves a 2056 Bit encryption not only on paper but in his head in under a minute to bypass lock-outs and other barriers put in his path by Love Machine.
• At one point in Yu-Gi-Oh! 5Ds, our heroes have to hack into the police files. After breaking standard security and encryption, the final security measure is figuring out the winning move in a game of Duel Monsters.
• In Yu-Gi-Oh!: Capsule Monsters, Yugi's puzzle-solving skills come in handy quite a few times as he solves puzzles the group encounters on their journey.
• Zatch Bell!:
  • The show spoofs this with Poosophagus (Unko Tin Tin). He guards Faudo's esophagus and threatens to drop the whole party in stomach acid if they don't all get a question right. Fortunately, most of his questions are really easy, when he remembers to ask one at all. He only asks two hard ones:
  • 829,735 × 962,527 = ?. Posed to Kiyomaro, a supergenius who calculates the answer in his head. ("It's 797,812,605,345!")
  • Prove Fermat's Last Theorem. A question that would be impossible for almost anyone on the planet, this was posed to Umagon, who can't even speak. Kiyomaro forces Poosophagus to give Umagon an easier question, a more conventional riddle. Mainly, because Poosophagus didn't know the answer himself.

Comic Strips

• The Far Side shows a math phobic's nightmare as being required to solve a Train Problem to get into Heaven.
• In Prickly City, Carmen is assured only the smartest people are allowed in an exclusive club.

Fanworks

• All That Glitters (Othellia): The route to a hidden cave that Hans claims contains a powerful magic artifact is recorded through a series of riddles.
• Harry Potter and the Underground's Saviour: Among the physical, magical, and teamwork puzzles the staff (and some Undertale characters) have set up are a few riddles, including: "How many eggs are used in French cooking." This goes unsolved until posed to someone from Beauxbatons, who repeats it in French, leading to the answer, "One, because one egg is un œuf." That is, "Enough".

Films — Live-Action

• Death Bell: The killer's questions are incredibly complicated, and everytime the protagonists fail to solve one, another student dies.
• Escape Room (2017): The puzzles in the escape room are fiendishly complex, with very little provided in the way of clues for solving them. One of the easier ones involved placing a series of magnets in the correct positions to solve the Riddle of the Sphinx.
• The tunnel leading to One-Eyed Willy's ship in The Goonies is filled with many booby-traps, such as the most memorable musical riddle. It makes sense since, during Willy's time, only people with a noble/high-born education would be able to read ''sheet music'. Even most musicians would only know how to play instruments, not read standardized notation.
• Indiana Jones and the Last Crusade:
  • The Knights of the Grail have protected their treasure with a series of tests, each more fiendish than the last, to ensure that no unworthy man may pass. The tests are multi-layered: to be proven worthy, one must find the clues to the tests elsewhere, interpret them correctly, and successfully act on the interpretation. Without the clues (which Indy's father found in his decades of research into Grail lore) it would be considerably harder, if not effectively impossible, to figure out the traps before they killed you. Those Wacky Nazis try to beat it with Trial & Error — but they've already lost over a dozen people to the first trap by the time Indy shows up, with Donovan shouting: "Get another volunteer." The final test, is simply of picking out the real Grail among all the dozens of fakes. No physical trait would give any advantage in figuring this one out. The correct one would be the cup looks completely unlike all the rest made only out of wood rather than gold. Also, anyone who is knowledgeable about Jesus would know he was the son of a humble carpenter and thus would likely not be able to have own a golden cup.
  • Even Indy has a brief bout of Idiot Ball and almost falls victim to the second trap. He realizes how it works - you step on the letters on the tiles on the floor to spell out "Jehovah" - but momentarily forgets at first that in the original Latin the name starts with an "I". After nearly falling to his doom, he gets it right.
• In Labyrinth, Sarah solves a classic Knights and Knaves puzzle. She can only ask a single question to one of two characters, one of whom always lies and the other tells the truth. She asks one what the other would say and gets a reliably false answer - too bad she thinks the reverse.
• The sphinx guarding Giants Orbiting in MirrorMask refuses to let Helena and Valentine through without answering riddles. However, as this is by Neil Gaiman, Helena's answer to the "4 legs in the morning, 2 legs in the afternoon, 3 in the evening" riddle was one of the performing dogs at her parents' circus, who walked around on his back legs as part of the afternoon show and hurt his paw partway through. Her counter-riddle was, "What's green, hangs on the wall, and whistles?" Answer: A herring. (That's an old Yiddish joke.)
  Gryphon: But a herring isn't green!
  Helena: You can paint it green.
  Gryphon: It doesn't hang on the wall!
  Helena: You can nail it to a wall.
  Gryphon: But a herring doesn't whistle!
  Helena: Oh, come on. I just put that in to stop it from being too obvious.

Gamebooks

• Constantly in Lone Wolf, where all your enemies use number problems to protect their stuff. In a gamebook with numbered sections, of course, number puzzles are the easiest to implement, and leave little possibility of cheating for the player.

Literature

• In Raymond Smullyan's puzzle book The Lady or the Tiger?, a king is inspired by the titular short story about a king who lets his prisoners choose between two doors, one leading to a beautiful lady and marriage and the other leading to a hungry tiger and death, but instead of leaving his prisoners' fate up to pure chance, he decides to reward intelligence by putting signs on the doors with true or false statements that make it possible for them to deduce which door leads to the lady through logic. However, his prisoners all prove to be smarter than he expected so he makes the logic puzzles increasingly more difficult until his final puzzle gives the prisoner nine doors to choose from and is literally unsolvable until he gives the prisoner a clue.
• In the Polish children's book Satan From The 7th Grade, protagonist Adam follows the clues and riddles that a Napoleonic-era soldier left for his brother, to find where he hid the treasure he brought back from the war. The attempted justification is that the soldier picked things only his brother would know, such as the book they read together when they were studying Italian.
• "The Most Precious of Treasures": Subverted. The protagonists must solve a room-sized Queens Puzzle in order to pass from one room of a dungeon to the next. Its purpose is to allow people in and keep beasts out, thus it's really a case of Only Sentient People May Pass; the implication is that the builder chose a well-known puzzle on purpose.
• In the novelisation of Earthsearch II, the puzzle at the climax is extremely simple but highly effective: the collected technological knowledge of the pre-Dark Ages Earth is guarded by a metal door that fits its frame too tightly to open, and is kept so by the slight heating from an embedded radioisotope; one must be observant enough to spot the extra warmth, smart enough to figure out that cooling the door will allow it to open, and sufficiently technologically advanced to achieve that on an overheated planet that has been in drought for over three centuries.
• The Polish novel Cylinder van Troffa, set mostly in a dilapidated old city inhabited by gangs. A small group of scientists, while in cold sleep, protects their base from the marauding uneducated hooligans with a door that demands solving a simple algebra problem to open. Once in a great while, the invaders manage to stumble across the answer... only to find themselves imprisoned in a small room unless they can solve a problem from derivative calculus. None of them ever managed that.
• In the Warhammer 40k novel The Iron Guard, this is a notable Weaksauce Weakness of the "changed". While they are quite cunning in other regards, their altered brains seem incapable of solving simple spatial puzzles. The unchanged survivors use this fact to construct barricades that most humans could easily dismantle by moving a few pieces around but the "changed" brains are incapable of reasoning out the puzzle.
• From Alice's Adventures in Wonderland: "Why is a Raven like a writing desk?" Lewis Carroll himself wrote: "Enquiries have been so often addressed to me, as to whether any answer to the Hatter's Riddle can be imagined, that I may as well put on record here what seems to me to be a fairly appropriate answer, viz: 'Because it can produce a few notes, though they are very flat; and it is nevar put with the wrong end in front!' The canonical answer, of course, is; "I haven't the slightest idea." Despite Word of God, people keep trying to "answer" the riddle. Some of the more famous "answers" include:
  • "Because there is a B in both and an N in neither."
  • "Because they both have inky quills."
  • "Because Poe wrote on both."
  • Another answer, in "The Cheshire" by Bill Kte'pi. The Genre Savvy title character says the outright truth, "It's nothing like a writing desk", which was the point of the original riddle; to show that the Wonderland inhabitants were quite insane.
  • Yet another, from a Christopher Stasheff book: "Both require quills to truly take wing." Naturally, this hasn't been a really valid answer for some time.
  • An annotated version of Alice in Wonderland suggested "It stoops with a flap," or a flap of wood that creates an incline on which to write.
  • Another answer: "You can't ride either one like a bicycle." It just seems to fit Wonderland so very well.
• Allen Steele's Labyrinth of Night features an alien complex on Mars entered through a series of locked doors with puzzles that require increasingly more intelligence to solve (and still-active death traps for the unwary). The archaeologists were baffled by the last chamber, which just played music, until they brought in a musician to jam with it, proving we have culture as well as brains.
• Cryptonomicon plays with this in order to show off Lawrence's intelligence early on the book. Lawrence has to take an admission exam for the US Army Signal Corps. The admission exam is not exactly difficult... until he encounters a question in the math section that basically says "A swimmer can reach up to 2 miles per hour. He is swimming against a river whose current has a speed of 1.5 mph. How much distance he could cover within an hour?". His reaction is to think only an idiot would believe the river follows a simple laminar flow, decides that this should be approached via the Navier-Stokes equations that model water flow using partial differential vectorial equations, and proceeds to fill 10 pages of mathematical scribbles until he can finally calculate a physically accurate answer. When time runs out, he painfully realizes he had completely missed the point of the question, and ends up having to beg the Army bureaucrats to accept his multiple pages of mathematical research that even wound up being published in a scientific journal.
• A variant occurs during The Dark Tower series, when Blaine, the insane supercomputer/monorail voluntarily takes the heroes to their destination, but agrees to let them live only if they can come up with a riddle he cannot answer. The catch is that Blaine has computer-access to the Dark Tower, and can therefore draw on the knowledge of riddles from ALL dimensions in existence. He is only defeated by BAD riddles, i.e. Eddie's horrible schoolyard jokes with no logical answers, which enrage Blaine to the point of blowing his own dipolar circuits.
• Dan Brown attempts this in The Da Vinci Code. There are such gems as the "strange script" of an unrecognised language that a symbologist, the granddaughter of a da Vinci expert and another da Vinci expert spend about five pages puzzling over. Two pages into this sequence, there's a copy of it printed — it's in da Vinci's trademark mirror writing.
• Pick a Deltora Quest book. ANY Deltora Quest book. Chances are you'll find a riddle that needs solving, some cryptic code that needs cracking or some other puzzle that needs figuring out. Probably more than one.
• Exploited in Diamond Dogs by Alastair Reynolds. The novella concerns the discovery of a sealed alien tower that can only be ascended by answering successively more difficult math problems in various chambers. The characters in the story are eventually forced to augment their own intelligence with neural implanting just to proceed. More sinisterly, the doorways between each chamber get smaller each time, forcing the characters to also modify their bodies to fit. The exploitation comes when the narrator realizes that the Tower probably doesn't have anything at the top. It exists solely to goad gullible intelligent species into exploring it. When they get to the top, the tower "harvests" them like a Venus Fly Trap.
• Discworld
  • Terry Pratchett has a lot of fun with this trope in Pyramids. Pteppic meets the sphinx of Greek Mythology — and gets into a three-page discussion about how the classic riddle ("What is it that walks on four legs in the morning, on two at noon and on three in the evening? — A man") doesn't make a lot of sense. The final version: "What is it that, metaphorically speaking, walks on four legs for about twenty minutes just after midnight, on two legs for most of the day (barring accidents) until at least suppertime, after which it continues to walk on two legs or with any prosthetic aids of its choice?"
  • Similar to the Lord of the Rings subversion, the plot of Thud! hinges on a magic cube that plays a recording when an unknown password is spoken aloud, that a Mad Artist who thought he was a chicken accidentally activated. The password turns out to be "Awk", which is Dwarvish for "Speak".
• Harry Potter
  • In Harry Potter and the Philosopher's Stone, Dumbledore banks on these to hinder Voldemort from getting to the Philosopher's Stone. Most of the puzzles placed to guard the Stone aren't truly puzzles (rather than leave a spell to ask you how to defeat Devil's Snare, Dumbledore let Professor Sprout decide that it would be much more effective to just set the plant on anyone who came through); notably, the exception is Snape's logic puzzle with the potions: "Most wizards haven't got an ounce of logic; they'd never get out alive." When Harry reaches the final room he realizes this is a Subverted Trope. It's made clear that Voldemort could never have retrieved the Philosopher's Stone from the Mirror of Erised, no matter how smart or clever he was in bypassing the other defenses. Only someone who didn't want to use it would be capable of doing so.
  • To gain entry to the living quarters of the House of Ravenclaw, one must answer an intellectual riddle. This is designed to help the Ravenclaws increase their intellectual capacity, so it's literally "only smart people may pass". It could even be intentional: perhaps Rowena considered all smart people honorary Ravenclaws? The Pottermore welcome message for Ravenclaw goes even further in this direction. It states that "it's not unusual" to see twenty or more Ravenclaw students trying to solve the day's riddle together, and that it's a great way for first years to learn from older students. It also says that Ravenclaws "learn quickly".
  • In the fourth book Harry stumbles on a sphinx in the labyrinth and has to solve its riddle.
• The Riddle Game in The Hobbit, since Gollum's kinda nuts. And in the "true" version, which is the only one you're likely to read nowadays, he intended to go invisible using the ring and kill Bilbo anyway. Then there's the in-universe debate on whether Bilbo technically cheated. It was concluded that "What have I got in my pocket?" shouldn't have been counted as a riddle at all, but it's arguably fair since Gollum accepted the riddle by trying to answer, even negotiating for three guesses. It should also be noted that Gollum demands three guesses, and guesses four things, though one of his guesses was correct at the time Bilbo gave the "riddle" (and had just become wrong a moment ago).
• In How Kazir Won His Wife, a king sets his daughter's suitor Kazir puzzles in order to assess his intellect. If Kazir fails, the king will not permit his daughter to marry Kazir.
• Journey to Chaos
  • This happens twice in A Mage's Power:
    • When Eric tries to enter the Temple of Zaticana, his path is blocked by the temple's guards. They declare that "No earthbound mortal may cross this temple threshold." Eric quickly figures out that instead of forbidding mortals to enter the temple, the statement means they want him to jump across, i.e. prove he is not "earth bound".
    • Eric's trial in Kyraa to earn Dengel's power involves knowledge from runes to dragon customs to clever use of magic.
    • The entrance to the Black Cloak's hideout is carefully hidden and guarded. To enter without setting off alarms, Eric has to use several spells in combination
  • In Looming Shadow, Eric has to pass several tests of magical knowledge to breach the security measures on Dengel's Lair.
• The Fellowship of the Ring subverts this with the gates of Moria; what's taken to be a riddle is just a literal instruction, although knowledge of Elven script is required to know that there is a password at all. You could accidentally open it by reading the untranslated inscription out loud.
• Raymond Smullyan also wrote What is the Name of This Book?, which had a chapter where Portia from The Merchant of Venice wants the gold, silver, and lead caskets to test her suitor's intelligence instead of his virtue so she has each casket inscribed with a true/false statement that makes it possible to logically deduce which casket has her portrait. Her daughter and granddaughter do similar tests, but a third descendant of hers in the far modern-day future subverts this by giving her suitor what look like logical tests identical to her ancestors' but are actually impossible to logically solve — she had actually decided long beforehand that she wanted to marry said suitor but, being a mischievous sort, wanted to have a little bit of fun with him first.
• In The Mote in God's Eye, the alien Moties have museums that are locked using astronomical puzzles. This is justified, since the museums are meant to help restore their civilization after the Dark Ages caused by inevitable, unstoppable population explosions, so the puzzles keep barbarian savages from busting the museum's lasers by using them to smash open walnuts.
• The Crown of All Things in The Last Watch was sealed in a most ingenious manner, but Merlin thoughtfully left a rather clever riddle behind. This was justified in that providing a hint was part of Merlin's idea of fair play, and it later turned out he had a very good reason to make it possible for someone intelligent to get their hands on it.
• Doubly subverted in Piers Anthony's novel Macroscope. The "Destroyer Signal", a radio signal picked up by a SETI search, appears at first to be a treasure trove of alien scientific knowledge that a few of the smartest humans may be capable of understanding, but turns out to be designed to overload their brains and burn out their minds with too much knowledge. Later in the book, it turns out that it is actually an "only smart and good people may pass" test, designed to destroy any intelligent mind not belonging to Perfect Pacifist People, to prevent all the tech (especially FTL Travel) from falling into the wrong head.
• Redwall series has many of these. The first book, for instance, has a series of riddles left by Martin the Warrior that lead to the location of his legendary sword.
• Downplayed and parodied in Roger Zelazny's The Chronicles of Amber series. Merlin encounters a Sphinx that will eat him if he can't guess the answer to a riddle. Merlin gives a plausible answer, but the Sphinx is looking for a specific one (that is virtually unknowable, relating to a then-obscure aspect of the story's world). Merlin argues with the Sphinx, eventually getting the concession that the Sphinx will let him pass if he can come up with a riddle the Sphinx can't answer. Merlin does so, with "What's green and red and goes round and round and round?" A frog in a Cuisinart. This is echoed in a later book when another guardian refuses to use this sort of test, but just for fun asks a riddle anyway — and it's the same one Merlin posed.
• Romance of the Three Kingdoms, Cao Cao is fond of word games, including leaving instructions in the form of incredibly involved plays on Chinese characters. The only problem was that the guy who solved them, Yang Xiu, made Cao nervous, both for his intelligence and for supporting one of Cao's younger sons rather than Cao's chosen heir. Cao Cao would have Yang Xiu executed when he interpreted one of Cao Cao's signal phrases (chicken neck) as a sign that Cao was preparing for retreat. It should be noted that Cao really was planning a retreat, but canceled the retreat so he could have an excuse to do away with Yang.
• Septimus Heap has the Wright of the Widdle in Queste, where the protagonists have to guess the meaning of some expressions that refer to some symbols to enter the House of Foryx.
• One of the gadgets used by the mysterious V.F.D in Lemony Snicket's A Series of Unfortunate Events is the "Vernacularly Fastened Door", a lock which can only be opened by answering trivia questions. It is a theme of the series that the good guys are more well-read than the bad guys.
• In Star Trek: Typhon Pact (part of the Star Trek Novel 'Verse), the home and office of the Tzenkethi Coalition's Autarch is inside a building with a flexible and highly changable design. To access the house requires contemplation of mathematical principles and aesthetics, to puzzle out the likely position of concealed openings. Agents of the Autarch are therefore tested every time they report to the building, and must demonstrate their worth by finding a way inside.
• In H. M. Hoover's This Time Of Darkness the main character has been an outcast because she is literate, in a world where people are trained from childhood to be stupid and ignorant. When she comes to a locked door containing a clearly written explanation of how to open it and disarm the guard lasers, she realizes with horror that whoever put the door there intended to kill anybody who went through who couldn't read - that is, if anybody else went through the door, they'd be killed.
• Reign of the Seven Spellblades: The test to enter the third layer of the labyrinth consists of the Battle of Hell's Armies, where two skeletal legions eternally reenact the ancient Battle of Diama (a Fantasy Conflict Counterpart of the Battle of Zama). The objective is to subvert the historical events so that the losing side instead wins, which requires the mages taking the test to both recognize the battle (Oliver only knows it because Pete had mentioned it offscreen while nerding out) and have enough knowledge of battlefield tactics to figure out how to change history. Though Professor Vanessa Aldiss proves it's also possible to simply brute-force the test: when the seniors reach the battlefield in volume 7, she's singlehandedly wiped out both armies.

Live-Action TV

• Game Shows examples:
  • Often used when giving away prizes to make sure that it's "skill-based" rather than luck-based, even if it's effectively luck-based. Generally the question is very simple, allowing anyone to answer it. There are entire shows based around this which intend to collect money from unwary viewers via premium-charged phone or SMS, giving away only a token prize for the winner. Another possibility is to make an "unsolvable" puzzle, such as "count the money in the picture" (when the answer is finally shown, it is revealed that there were coins in the picture completely obscured by other coins) or "find the names of 3 bands in the letter square" (which is filled with misspelling of popular band names and the answer is 3 obscure bands with nondescript acronym names). Multiple callers can attempt to answer but generally none will succeed, so nobody gets the prize because they weren't "smart" enough.
  • In some places (Canada, for example) the law prohibits "gambling" (e.g. a lottery, even if no entry fee is charged) but permits "contests of skill". Apparently, correctly answering "2+2=?" makes it a contest of skill as far as the law is concerned, even if the winner is then randomly chosen from the correct entries (i.e. all of them). In other words, Loophole Abuse.

---

• The first episode of Are You Afraid of the Dark?, "The Tale of the Phantom Cab": The woods are haunted by the ghosts of lost hikers and campers who found Dr. Vink's cottage. He would send them to board the Phantom Cab and die in a replica of the same crash that killed the driver. Why? Because none of them (until the two boys in the tale) could answer his riddle: "What has no weight? Can be seen with the naked eye? And if you put it in a barrel, it will make the barrel lighter?" A hole. Other common entities that satisfy this description: fire, "A flashlight beam."
• In Babylon 5, an alien probe promises to transmit its vast store of knowledge to any species that passes its intelligence test. It's actually a bomb that will destroy the first planet to answer correctly, taking out any up-and-coming civilization that might one day rival its creators.
• Blake's 7. In "City at the Edge of the World", the descendants of a civilization that descended into barbarism have to get through a door leading to a New Eden (it's a long-range teleporter to a new colony planet). They convince a gang of Space Pirates that what remains of the planets' wealth is sealed up behind the door. They know these criminals aren't clever enough to open it themselves, but they can get hold of someone who is.
• CSI: NY: "Death House" involves an abandoned penthouse full of deadly booby traps. In order to avoid them while searching for a trapped victim, the team has to follow clues throughout the apartment to first locate, then solve, two hidden riddles.
• Doctor Who:
  • "The Dalek Invasion of Earth" contains a particularly nice (or nasty?) example. Human captives of the Daleks are imprisoned in cells aboard their ships. The Doctor examines the door-locking mechanism and works out a way to deactivate it and thus escape. He does, and it turns out that the mechanism is actually an intelligence test — those smart enough to escape their cells are potentially dangerous and are sent to be turned into RoboMen.
  • The Cybermen do something similar in "The Tomb of the Cybermen". Anyone skilled enough in symbolic logic to get into the tombs and awaken the Cybermen is clearly a good candidate for conversion into a Cyberman.
  • "Death to the Daleks" has a test which takes the form of a series of death traps, killing anyone not smart enough to find the solution quickly. The Doctor speculates that people who can pass might have some other knowledge that might benefit the city.
  • "42" has a bunch of locked doors that require trivia questions to open. In theory this is a passcode system, not a puzzle — the crew of the ship in question set the questions with the intent to be the only group who could give all the right answers. Notably, one of them set his favourite colour as an answer. However, "the crew's changed since we set the questions", the current crew reset the questions while drunk, and some of them have died horribly, explaining the fact that all the questions seen aside from the guy's favourite colour apparently have to be answered by the Doctor or Martha. Granted, this episode is set far enough in The Future that a question referencing The Beatles is listed in the category of "Classical Music".
• Subverted in Double the Fist. The Womp has to get past a pair of "one always lies and the other tells the truth" guardians, but he's Too Dumb to Live and when the increasingly frustrated guards try to explain how the puzzle works the liar accidentally tells the truth, causing his head to explode.
• Subverted in The Librarians 2014 "...And the Rise of Chaos", in which the DOSA vault has three locks. Ezekial finds them unhackable, and while Cassandra's has a maths problem and Jake's has an ancient riddle, entering the answers doesn't work. They eventually realise that, since they're smarter than anyone at DOSA, and DOSA is specifically trying to keep them out, the locks are designed to stop smart people from passing. Instead of the complex number she originally came up with, Cassandra realises the simplest solution is 3, Jake enters the exact opposite of the riddle's answer, and the password for Ezekial's lock? "Password".
• This happens on Noel Fielding's Luxury Comedy, when Fantasy Man and Chief Woolabum want to cross the river but are stopped by a schizophrenic flag named Bobbatron, who demands the answer to a mind-bogglingly bizarre riddle: "If it takes a year to drink a horse, how long does a Spanish priest have to cry for, when rolling up a hill against a north-facing breeze... bearing in mind that it's winter and dark, and the priest is covered in ball bearings and his own shit?" Naturally they Take a Third Option, pushing Bobbatron into the river and crossing the bridge as if nothing had happened.
• Parodied again in The Office (US), where Dwight keeps asking Ryan one logic riddle after the other. Ryan answers them so quickly that Dwight barely has the time to say the first few words before he gives the correct answer.
  Dwight: A hunter-
  Ryan: It's a polar bear because you're at the North Pole.
  Dwight: DAMMIT!
• Dr. Nigiri sets one of these as final barrier on his plan to takeover the console in the Pixelface episode "The Problems of Dr. Nigiri". It falls to Sgt. Riley — as the only one not brainwashed — to attempt to solve it.
• Probe's "Computer Logic": When Mickey is trying to get into Austin's private workspace, the electronic lock issues a Limerick challenge that appears to be testing the visitor's intelligence but is actually designed to be impossible to solve. There's a response that will unlock the door, but its exact form can't be arrived at by logic or any other systematic process. Mickey gets through by sheer luck; confronted with a puzzle she barely understands and has no idea how to solve, she mutters a dejected remark—which happens to be the required pass phrase.
  Austin James (recording): There once was a poet named Gunderson, whose rhymes were exceedingly cumbersome. With each botched refrain, his complaint was the same, Blah, blah... blah, blah... blah, blah, blah! You have ten seconds to give me the last line to get in. Otherwise, go away.
  Michelle Castle:...How do I get into these situations?
  (door opens)
  Austin James: How did you get in here?
  Michelle Castle: Me? I... uh, I finished the Limerick at the door...
  Austin James: That's impossible! Nobody can finish it. It's too idiosyncratic. It doesn't even rhyme! I made it to keep people out.
• Stargate-verse
  • The ability to identify the first six digits of pi and the radius of a circle guarded an Asgard communication device that would have allowed the populace of a world to speak with their "god" and learn all kinds of things about the Universe in Stargate SG-1. It's justified in that Thor didn't want to speak directly with a society until they achieved some kind of scientific knowledge. He deduced that if they were smart enough to understand the concept of pi, they could handle learning their "god" was actually a Sufficiently Advanced Alien (albeit one who genuinely cared for them and acted as a protector). If they could not, then You Are Not Ready...yet.
  • In "The Tomb", a ruined temple to the Goa'uld Marduk was blocked by a great stone door inscribed with the Babylonian creation myth. Opening the door required pressing the sections of the text that were incorrect, things that in theory only the priests of Marduk would know. Fortunately Daniel Jackson has studied Babylonian mythology and reads the language.
  • The Ancients, or at least Merlin, were also fond of using these to guard superweapons. The Dakara Superweapon, built by The Ancients, capable of wiping out all life in the galaxy, requires understanding of Ancient language. Failing that, using the notes of someone who does will also do.
  • In "Avalon", Daniel has to solve a riddle to figure out which pot contains a gold coin and Mitchell gets stuck trying to translate an Ancient language.
  • During the quest to find the Sangraal, The Team had to use four virtues to reach the Sangraal and one of them was wisdom.
  • Stargate Atlantis had such puzzles, like finding the ZPM by using the numbers 1-9 to make a Magic Square Puzzle, part by desperation, part by realizing the significance of the number 15.

Music

• Bull of Heaven were known on occasion to troll their fans in this way. Examples range from requiring the listener to change a file extension to .mp3 in order to listen to a song, to a extracting a Matryoshka doll of compressed files, to password-protecting the song without giving any clue as to what the password is, to all three at the same time. What's more, if someone guessed the password and posted it on the Internet, they would change it and reupload the file.

Radio

• In Season 2 of the BBC Radio Drama Earthsearch, the protagonists finally succeed in finding Earth, only it's a wasteland with what remains of humanity occupying a village next to a tower holding a repository of all human knowledge. The single door is designed so it can only be opened after humanity has regained a certain level of scientific development. The door contains a radioactive isotope that heats the door slightly so it jams in the frame, requiring refrigeration technology to reverse the effect.

Tabletop Games

• Inverted in Yarra, River of Death, an (in)famous Polish module penned by Andrzej Sapkowski. At one point, the characters have to haul their barge over shallows made out of shoulder-deep mud teeming with maggots and leeches. After few moments inside the mud, everyone is required to make an Intelligence check. If they pass it, they instantly get a panic attack due to all the filth crawling all over them and won't be able to help that day anymore. In the same time, to haul the barge over, it requires a Strength value impossible without at least 3 average characters working together, thus making a Dumb Muscle PCs very handy. That moment is responsible for roughly third of all Total Party Kills during the scenario, as it's perfectly possible to get stuck there forever and starve to death or die out of malaria. And no, no sudden flood is going to save the party.
• Exalted
  • In the Time of Tumult the players have to select the wrong answer in a classic Knights and Knaves puzzle. This is fair since the PCs are navigating a maze specifically designed to kill anyone but the creators and they know it. Only Really Smart People may pass.
  • Exalted later plays it straight and justifies it in Under the Rose, which has a section of puzzle-based deathtraps designed by Autochthon, the Great Maker. A side-note mentions that as part of his inhuman mindset, Autochthon is physically unable to design any form of defenses without including puzzle-based deathtraps.

Theatre

• Invoked in Jasper in Deadland; Cerberus initially thinks that eating a living person like Jasper will give it some insight into what it means to be "alive". To avoid this, Jasper realizes he can just explain to Cerberus what it means to be alive.

Video Games

• Parodied in the PS1 game Shadow Madness; at one point, the heroes encounter a talking stone mouth located in a crypt that's been unoccupied for centuries. When it tells them to answer three questions in order to pass, one of the heroes asks why, to which it responds with, "You'd be bored too if you were me, honey."
• In the game Brothers Pilots, a fridge is locked by a puzzle. After you open it, a cat comes out and opens the door your characters were unable to open by simply pushing it (your characters try to pull it). Apparently, solving this puzzle was simpler than opening an unlocked door.
• Chinatown Detective Agency, which is kind of a Spiritual Successor to the Carmen Sandiego franchise and a borderline Edutainment Game for grown-ups, unsurprisingly runs on this, particularly throughout the art theft subplot. The password to the rare book case in the library involves pulling switches coded by characters from major novels, a secret door has to be opened by correctly assembling Bosch triptychs, etc.
• Amiga game The Chaos Engine (Soldiers of Fortune on consoles) features fairly inventive puzzles which can only be interacted with by shooting them. In rooms full of enemies. Often, you'll have solved the puzzle without ever noticing it existed.
• In Anachronox, to board the shuttle to Sunder (a Planet of Hats populated by scientists), the heroes must pass the Brain Bouncer, who demands explanations of complex scientific theories to ensure that the hopeful passenger really is a scientist of high caliber. This is then parodied when your helpful robotic buddy downloads the entire galactic scientific database into his memory, and you have to pretend to speak a language that the bouncer doesn't, so your robo-buddy can helpfully "translate" for you. Of course, there are two additional (humorous) swerves: the bouncer speaks all known languages (forcing you to "invent" a language), and at one point, after provided an answer that can be as short as three sounds and as long a twelve sounds, your robo-buddy prattles on for long enough that the scene fades out.
• This is the central premise behind the gameplay of Another Code: For some unfathomable reason, the designers of the mansion on Blood Edward Island thought that it would be more efficient to use logic puzzles instead of keys or handles.
• There are a handful in Avencast: Rise of the Mage: two requiring the player to figure out biographical information at the subjects' tombs and another only allowing access to an art exhibit to someone smart enough to reconstruct an artwork.
• Baldur's Gate II has several such moments. The oddest riddle is one that makes sense as game dialogue but would be quite horrible if someone came to you and spoke it like this:
  A princess is as old as the prince will be when the princess is twice as old as the prince was when the princess' age was half the sum of their present age. Which of the following, then, could be true: the prince is 20 and the princess is 30, the prince is 40 and the princess is 30, the prince is 30 and the princess is 40, the prince is 30 and the princess is 20, or, they are both the same age?
  • The prince is 30, the princess is 40. Any age with the same ratio will also do.
• Banjo-Kazooie's final level is a board game asking questions about various events in the game as well as matching sound effects and jingles to what they mean.
• Betrayal at Krondor has a great many chests called "Wordlocks" that are essentially combination locks with letters instead of numbers, and they have riddles on them. The answer to the riddle is the combination, though one sidequest-relevant chest follows another trope.
• The Black Mirror series is full of puzzle lock mechanisms and safes with Only the Knowledgable May Pass solutions whose presence in the game world strains credibility. This is Lampshaded in Black Mirror II where at one point the PC sees an "escritoire without a puzzle lock" and muses that it must be an old model.
• Born Under the Rain: Inside the Northern Desert Sphinx is a series of bridges that need to be unlocked to reach the boss of the area. One of those bridges are unlocked by a math puzzle where four numbers out of twelve options must be chosen to add up to 19.
• Brain Lord is Exactly What It Says on the Tin, and EVERY puzzle that doesn't involve 'kill all enemies in the room' will genuinely test your reasoning ability....or patience, if you go for trial and error.
• In Conquests of Camelot, there were several Copy Protection-type puzzles which required not only having the manual but correctly interpreting it as well. One part early in the game played this more straight, featuring a magic barrier that could be passed only after talking to some stones and solving the riddles they gave you.
• In Cultist Simulator, in order to pass through the Stag Door in the Mansus, the protagonist will have to answer its riddle.
• Darklands: The dwarf logic puzzles. (With one exception, which due to writer error is a Guide Dang It!.)
• Used on you (as the Featureless Protagonist) in Dark Tales: Murders in the Rue Morgue. When you first meet Detective Dupin so that you might solve the murder together, he puts you through your paces, solving a series of puzzles in and around his house. He wants to make sure you're up to the task before he lets you come with him.
• In Dead Space 2, the Marker tests all that it comes into contact with by transmitting a signal that either drives people insane or gives them the knowledge they would need to create a new Marker.
• Devil May Cry 3: Dante's Awakening has the aptly-named Trial of Wisdom with multiple doors that are each marked with a different number of lights. To proceed, they have to be entered in a certain order, and your only clue to figuring that out is a reference to the Riddle of the Sphinx. Easy enough to solve for those familiar with it, and utterly baffling for anyone who's not. However, this section can be optional if you only wish to proceed to the next area (as only two out of three Trials must be passed to break the rubble blocking the gate), but it's mandatory only if you wish to acquire the Artemis weapon.
• Discworld Noir looks like it's headed for this when an ancient guardian wants to ask you a riddle to see if you are worthy to receive the MacGuffin. Then come the subversions, first by the guardian who happened to forget the riddle during his 400-year-wait (but still insists to only hand the item to those who answer it) and then by Lewton who points out that someone of the unworthy faction would just hack the weaponless guardian to pieces. As he's in somewhat of a hurry, he gives the guardian the option to hand over the McGuffin — or he'll just pretend to be unworthy enough... The guardian relents.
• Disgaea 2: Cursed Memories has a minor boss in the Inevitable Tournament tries to challenge the heroes with the mother of all geo puzzles, causing the page quote from Tink in regards to Idiot Hero Adell. Adell takes one glance at the puzzle and states its correct solution without missing a beat, freaking out the puzzle creator and the rest of the heroes. Of course, to the player the real puzzle is getting to the solution that Adell pointed out. It's at the end of a maze of No Entry panels guarded by monsters. Although if you have enough range on your spells (which depends on how many times you've cast it before) you can hit it from the starting position.
• In Dishonored 2, the lock on Aramis Stilton's manor is designed by Kirin Jindosh, and is so fiendishly complex that nobody has been able to crack it - it even indirectly led to one character's mutilation. When you get there to try yourself, it's...an incredibly simple logic puzzle of the kind found in brainteaser and Crossword Puzzle books, and you only have to solve half of it anyway. Apparently nobody in the entire Empire except the protagonist is smart enough to go through a simple process of elimination, which honestly explains a lot about the setting.
• In the Dragon Age II DLC Mark of the Assassin, the vaults of Chateau Haine are like this. Normal people keep their valuables safe with locks and, perhaps, guards. Duke Prosper prefers to use puzzles.
• Dragon Age: Origins:
  • At one point, the character must complete a relatively easy puzzle using party members to stand on plates to create a bridge to reach the ashes of the prophet Andraste. If Alistair is in your party, he'll comment on this:
    Alistair: Maker's Breath, Andraste only favored the clever, it seems.
  • Leliana also jokes about how you may have to "all join hands and sing a happy song to get across." The quest also has a room full of spirits who give you riddles and attack you if you answer incorrectly. Some of them will let you off if you admit you can't answer - emphasis on some.
  • The Mage origin story has a sloth demon that you can either fight, or correctly answer his riddles.
• Dr. Brain is built on this, with plenty of puzzles, labyrinths and other challenges. However, the doctor isn't trying to keep you out, just test you to see if you're good enough to become his assistant.
• The Elder Scrolls:
  • Riddles are recurring puzzles in early installments, though later games forgo them in favor of more conventional puzzles. According to various in-game books, riddles contests are a popular pastime amongst the upper crust, who use them to show off their wit and intellect, implying that these riddle puzzles are based out of that custom.
  • In The Elder Scrolls: Arena, all the dungeons with pieces of the Staff of Chaos (and clues to said pieces) have doors and gates that are locked away with riddles. For example, one of Labyrinthian's riddles is "Two bodies have I, / Though both joined in one. / The more still I stand, / The quicker I run...",^note The answer is an hourglass while Halls of Colossus has one where you convert letters into numbers to figure out someone's age.
  • Various doors in Level 2a of An Elder Scrolls Legend: Battlespire are also impassible unless you answer a riddle. Thankfully, there's also a copy of The Kendhall Book of Riddles in the study, which has answers to all of them.
  • The "Courtesy" quest in The Elder Scrolls III: Morrowind has you defend the honor of the Imperial Legion by answering some riddles. Unlike the previous games, the riddles are actually multiple choice questions, but the correct option doesn't appear unless you have a copy of The Red Book of Riddles in your inventory (the book doesn't actually show you any riddles, so your character is presumably looking them up) or your Intelligence stat is 50 or higher.
  • Skyrim: Many of the ancient dungeons have various lever and button puzzles, often with deadly traps to go off if you don't get the solution right. Often, the combination is shown in plain sight, but people still get it wrong. The huge puzzle doors are especially notable, as they require both a key and a combination, but the combination is engraved on the key. However, one book actually points this out - the puzzle doors aren't intended to keep explorers out, but to keep the undead draugr in. The bare minimum of intelligence required to figure out how to open the door is expected because draugr are practically mindless and can't even accomplish that.
• In Exile II, to address the Vahnatai Council you must complete as many as three tests^note Depending on which puzzles you solved in the previous chapter, you could be required to do all three, or none at all: the Test of Strength (a series of combats), the Test of Speed (outrunning a wall of quickfire), and the Test of Mind (word games, math puzzles, riddles, and a maze). You might suspect that most players would skip the latter if they had a choice, but there's also nothing stopping the player from going after all three even if they're not required. In the remake, Avernum 2, the Test of Mind was replaced with the Test of Patience (a Block Puzzle).
• Fallout:
  • In the early games, this is character-based instead of player based, with Intelligence attribute checks, or various skill checks. Ironically, some story quests are actually much easier if your character is extremely stupid since the quest givers will realize that you are to too dumb to complete them and will do it themselves.
  • In Fallout 3 a sidequest in what's left of the Smithsonian requires you to answer trivia questions on American history to open a safe containing some loot. Another unmarked sidequest requires you to pick out prime numbers from lists to spawn a unique assault rifle.
• Fatal Frame has several doors were locked with numerical combination locks. This wouldn't be so bad (the combinations are hidden in various notebooks and diaries hidden around the mansion), except that the lock itself has the numbers written in kanji and in an archaic arrangement (counterclockwise with "zero" in the top position). Only a minor example for Japanese players, but for Western players this is Guide Dang It! territory (at the very least, much harder than the developers intended the puzzle to be). Fortunately, the Xbox remake addressed this by changing the lock to feature numerals rather than kanji.
• Final Fantasy:
  • Final Fantasy VI had a very interesting minigame built into the plot, wherein the team has to sit down for dinner with Emperor Gestahl and make small-talk. Several questions are asked of the player, for toasts and such, most of which offer three possible answers: sucking-up, magnanimous, and vindictive. He also answers questions about some plot-points, and then quizzes on which one was asked first. The game goes on through the dinner no matter what; since it's not possible to "lose", it's not exactly a critical puzzle, but "winning" nets the player lots of nice rewards. The puzzle is figuring out the right answers - each has a score attached to it, with the rewards based on the total earned. As the Emperor is trying to make amends for his past actions, you shouldn't pick the options that make light of his apologies or, you know, offend the host himself. As the other Returners are present, you shouldn't want to offend them either by sucking up too hard for their previous enemy, which is why the middle-of-the-road answers are best.
  • In Final Fantasy X-2, there's a minigame called "Sphere Break". This game revolves around using coins to come up with various combinations of numbers with multiplication and addition. Finding the coins in the game proper is fairly easy, as you just wander around playing the desert minigame until you find the coins you need. The Sphere Break game itself requires quick mental math, something that no amount of grinding or walkthroughs will ever prepare you for. And to add insult to injury, some of the game's best Accessories, as well as a few Garment Grids and the Lady Luck Dressphere, can only be won by playing and/or winning Sphere Break matches, not to mention that the minigame itself can be abused for item farming.
  • Final Fantasy XIII-2 has the temporal rifts, which offer you one of three puzzles; Tile Trial, Crystal Bonds, or the Hands of Time. Tile Trial is fairly painless, but the harder Crystal Bonds tend to demand very quick reflexes, memorization, and a bit of luck. As for Hands of Time, it's the only one that isn't mandatory to complete the game, and when you attempt one, you'll see why. Etro help you if you decide to go for 100% Completion, because you have to solve several of them, often going up to thirteen numbers.
  • An alliance raid boss in Final Fantasy XIV has a phase where it reduces everyone's HP to the single digits and builds up an attack that will kill you unless you match your altered max HP in multiples of X with X being whatever number the boss mentions. Four circular pads on the floor boosts your HP by 1 to 4 to help you solve the math problem. The real difficulty comes in later where the boss does the same gimmick again, but replaces multiplication with having you match your HP to prime numbers.
• In the Interactive Fiction game Gateway, you need to solve a puzzle to get to the first Heechee device. The puzzle ("which of these is not like the others") was put there so the species on the planet in question couldn't get at the device before they became smart enough. Hence, Only Smart People May Pass, which was its point.
• Guild Wars:
  • In Guild Wars: Nightfall, the Dasha Vestibule mission has a room with six pedestals with composite numbers and four with primes. The player must chose two composite numbers such that all four primes are factors of one of the chosen numbers.
  • Used as a joke in the "Elusive Golemancer" mission in Guild Wars: Eye of the North. "We designed the traps to keep less intelligent creatures out. We Asura have no problems with them. You, um, you should be fine. Yeah. You'll be just fine."
• The Journeyman Project has one scene where a murderous robot is launching nuclear missiles and you have to deactivate the silos before said missiles launch. To do so, you have to navigate a holographic globe of the world and find the city and country of origin that the computer tells you about. It's effectively a simple geography check, but woe to any kid back then that didn't know their geography or lacked an actual map of the world to cross reference.
• Killer7 has a number of strange puzzles in bizarre and unlikely places.
• The Kingdom of Loathing does this with the Altar of Literacy that people have to pass to gain access to the chat. Its trials include typing a sentence and answering the "unspeakably difficult" trivia question "What colour was George Washington's favorite white horse?" Even though it's meant to be a comical RPG in general, it is an unspeakably good idea.
• In King's Quest VI, in order to get anywhere beyond a small beach on the Isle of the Sacred Mountain, you have to bypass a little obstacle aptly called the "Cliffs of Logic". That the Cliffs are an ancient test of intelligence is only the in-character explanation; out of character, the game practically demands you look up the solution in the guidebook that came with it.
• The Zelda series has many of these in every dungeon. Forget fighting monsters, the meat of the dungeons is pushing around blocks in a grand scaled puzzle box to get to the MacGuffin. In The Legend of Zelda: Twilight Princess, there is a point where Wolf Link, trying to enter the sacred grove that houses the Master Sword, is confronted by two malevolent-seeming statues. The statues explain that if he can get them back onto the spots where they're supposed to be standing, he can enter. Since the one of the statues will mimic his movements and the other will do the opposite, he has to jump around in the correct sequence to get them to shift onto the indicated squares and thus open the door.
• Live A Live has the Trial of Wisdom dungeon in the Final Chapter. You're only allowed to challenge it if you have Cube in your party, otherwise you are merely told "those who rely on strength may not enter here". There are no battles to be had in the dungeon, and you're instead tasked with solving puzzles to get an ultimate weapon at the end of the dungeon. That said, there will be a Superboss waiting for you if you return to the dungeon after clearing it.
• Lufia II: Rise of the Sinistrals:
  • Every floor of every dungeon, cave, castle, tower or mansion is littered with puzzles of all sorts that you must complete to open doors. It gets so extreme that one can reasonably argue that Lufia II is a puzzle game with a large story and RPG-elements in it.
  • There is also a secret room in one of the later dungeons that has "the hardest puzzle in the world" which involves sliding platforms around and around for about 20-ish rounds, until you have the platform with the treasure chests filled with neat loot in front of you.
• All over the place in Machinarium; it seems that every other mechanism or locked door in the city is protected with one or another classic logic puzzle.
• In MediEvil, the player can only gain entrance to the Asylum after answering a number of riddles "so perplexingly complex that no man has ever solved them" posed by Jack of the Green. Interestingly, the puzzles themselves are fairly easy to figure out, except for perhaps the last one. The real problem is in figuring out how you're meant to answer them.
• The Might and Magic series had third game Isles of Terra, which loved riddles. Statues, zombies, and random folks will ask riddles and will reward the player with story tidbits, such as how to complete certain quests (Princess Trueberry has the Golden Alicorn) or avoid pitfalls (If you take a Pearl of Youth and Beauty to the Pirate Queen, she won't steal the party gold). The Lords of Arachnoid Cavern are the largest example: Lord Might tells the party to start with his number, and then go in an order that Lord Word might find agreeable, which implies going alphabetically)
• The Myst: The D'ni people in general were enamored of puzzle games, and Atrus picked up on it quickly when taken to the ruined city. It's lampshaded in a parody of Revelation, by a frustrated Stranger working on the fireplace puzzle:
  "I mean, does he [Atrus] not mind people breaking in as long as they have an IQ of 150 and brilliant abstract logic skills? No wonder this place is always being smashed up by twisted geniuses seeking revenge on the entire family..."
• Oracle of Askigaga: At one point of the game, you have to correctly pick out the true assassin within a small group of people in order to proceed.
• The first Pajama Sam game, No Need to Hide When It's Dark Outside, had the "Brain Tickler," a brief quiz show narrated by two talking doors, Wink and Blink, inside Darkness's house. To progress, Sam has to answer one question correctly in four different quiz categories. Most of the questions are simple enough for the game's target audience of young children, ranging from basic math to geography. The fourth category, however will always be 'The Land of Darkness,' and the question asked will be about a certain location the player may or may not have visited yet (for example, it may ask what the reading on the water meter is in the mines near Darkness's house), and if they haven't, all the possible answers are incorrect until the player explores those areas.
• In both Paper Mario and its sequel, there are puzzles where you're required to answer questions about the game to proceed (or at least, to avoid a tricky boss fight).
• Subverted in Planescape: Torment: the night hag Ravel Puzzlewell asks everyone who seeks her out the sphinx-like question, "What can change the nature of a man?", then tortures and kills everyone who gives the wrong answer. Turns out she wasn't looking for a particular answer. She was interested in the response of a particular person, that of her former lover. The Nameless One's "best ending" has him stating that many things can change the nature of a man. Belief, regret, love, etc. Then he gets to revive all his companions (except the evil pyromaniac mage) and say goodbye before enlisting in the Bloodwar.
• Pokémon:
  • Played with in Diamond / Pearl. One Gym presents you with three doors and a mathematical question - you go through the door associated with the correct answer. The thing is, the questions are so easy - and the main character is even given a calculator right at the start of the game - that the trainers who battle you behind the incorrect doors assume you deliberately got the answers wrong. One girl is pleased that you decided to battle her; another cheerfully agrees with your 'battle everyone' philosophy; and one boy complains 'why don't you just answer the questions properly?'. Then there's the last question: "What was the answer to the first question?" If you weren't really paying attention because the questions were so easy, you'll likely get it wrong.
  • Played straight in the rest of the games such as the second-last Gym of the first generation has a series of doors that can only be opened by answering a series of general-knowledge questions pertaining to the Pokemon world. Failure to answer correctly results in you having to fight the trainers guarding the doors — and since they give extra experience and cash anyway, why tax your brain? The questions are for those who don't want to battle the trainers. You don't even need to answer the questions. Talk to the trainers to battle them and the door automatically opens if you win, whether you answered the question or not.
  • Also in Pokémon Sun and Moon, you have to play an audio quiz with Sophocles as part of his trial, due to the power required to run everything else being used up by his equipment to summon the Totem Pokemon. Failure to answer the question correctly results in Sophocles getting fried; answering correctly gets you a battle, with the Totem Vikavolt being number four.
• Portal. The puzzles at the beginning exist not to test the Portal Gun, but to see whether Chell is smart enough to use it.
• Professor Layton has many of these.
  • Penny Arcade parodies it, suggesting it's a "Logic Opera": "every person you meet breaks into "puzzle" the way that Viking ladies tend to break into song, out of nowhere." The first game in the series, Professor Layton and the Curious Village, actually turns out to have invoked the trope: a guy deliberately set up all the puzzles to test the intelligence of those seeking his treasure.
  • Becomes literally so as in every single game there is a guard of some sort preventing you from entering the dungeon(s) if you haven't completed a certain number of soup can puzzles, and you thought you could ignore the hard ones and only miss out on 100% Completion!
  • In the Azran Legacy game, there's the Azran tombs where you have to solve the ball-rolling puzzles to get from room to room. Did Hershel never think to jump over that hole? No? How about follow Randy, who's pushing the balls? No? Only the ridiculously idiotic intelligent may pass, it would seem here.
• Likewise, Quest for Glory IV has Dr. Cranium (supposedly an ancestor of Dr. Brain), whose lab is behind four different puzzles, though all but one are interconnected. Unlike his descendant though, Cranium just wants his privacy and is sufficiently impressed when you enter. He even has a sign on his front door that all but names the trope.
• Rakenzarn Tales is fond of doors that only open when you Enter Solution Here, usually by answering a nearby riddle or unscrambling a clue from another area. Plot-required ones are a little easier such as in Chapter 3 where you have to figure out what a place called the Water Sanctuary considers the most important thing, with the sidequest ones being a wee bit more difficult.
• Resident Evil: why does a scientific lab require you to manipulate chess pieces to open a locked door? No one knows. The series handwaves it by saying that Spencer, the man who designed the mansion, was insane and paranoid.
• Rogue Galaxy: There's a skyscraper sized block puzzle guarding ancient ruins.
• Shining the Holy Ark has a puzzle involving weights and scales before you can enter the dungeon proper. Also it has the infamous stone puzzle.
• Silent Hill:
  • The franchise has a lot of this, but Silent Hill 3 stretches it into true absurdity with a puzzle requiring an astoundingly thorough knowledge of the works of Shakespeare to pass (on Hard mode). Of course, it's Silent Hill we're talking about here — making sense is purely optional and any puzzle that can be explained with sufficiently elaborate Epileptic Trees (like, say, a 20 page forum debate between fans who have memorized the game) is obviously logically sound by the laws of the place.
  • There's also quite a few verbal puzzles in the game that are obscenely simple if you're familiar with the source. The source may be a common Japanese nursery rhyme that makes it impossible for American audiences to solve without some sort of reference, or aspects of American culture that seem blatantly obvious to us but are downright Insane Troll Logic to the original Japanese audience. Which, given the whole confusing nature of the series, may be entirely intentional.
• Star Wars: Knights of the Old Republic:
  • Arithmetic puzzles get used for everything from decryption to demolitions.
  • The trivia questions both the ancient Rakatans and Darth Revan used to cover the tracks to their secret base. There's also a Schmuck Bait sidequest that is solved by winning a riddle contest with a prisoner stuck in a mind trap.
  • Several puzzles in KOTOR are in fact classic puzzles given a more context appropriate reskin. The damaged extractor control system on Manaan is the same "measure 4 liters using only a 3 liter and a 5 liter container" seen in Die Hard 3 (it can be bypassed, but doing so gets you banned from the planet and gives you dark side points), while the Sith tomb's energy ring transfer puzzle is really a jazzed up Towers of Hanoi.
  • The Brotherhood of Shadow game mod has a wicked one. A Czerka employee was trying to seal off the mining tunnels from his crazed co-workers. He set up a system requiring accessing several terminals in succession and answering questions about "basic galactic history" (read: lore from Star Wars Legends) in order to open the doors.
• Super Mario RPG:
  • While slogging through Bowser's Castle toward the end, Mario reaches six doors, leading to instances of three kinds of challenges. Two are straight combat, two are platforming action, and two are a gauntlet of dime-store brain teasers, hosted by a green Hammer Brother named "Dr. Topper". On the menu: peg-jumping puzzles, counting games, trivia quizzes about the RPG itself, and an infuriating "Who finished what place in a triathlon?" word problem. You only have to pass four of six doors, but randomly speaking, you'll have to face at least one of them.
  • There are some in the Sunken Ship. A series of platforming challenges give nautically themed clues to a six-letter word puzzle to enter the Boss Room. None of the challenges have to be completed, if a player can suss out a fitting word from the given letters. Both the quiz-gauntlet and the word puzzle are relatively simple affairs, but for younger players, they could be pretty stymieing, as they relied on critical thinking and some outside information.
• Used over and over again in Tales of Eternia, the first Tales game with the bright, involved, and unique sort of puzzles that also contributed to Tales of Symphonia being the hit it was. Then, without warning, subverted at the beginning of Volt's ruins: The Smart Guy Keele has been left behind, so while the rest of your party is busy scratching their heads and staring at the obtuse riddle on the front gate, Max walks up to the door and body-slams it down. The rest of the dungeon, of course, is full of puzzles, but damn if the scene wasn't hilarious.
• Trauma Center: New Blood: to escape a pit filling with water, the two doctors and nurse that have refused to help the Big Bad have to solve a complicated puzzle. To do so they have to "connect the four friends," meaning they connect the pegs that match in color to each other. It's surprisingly difficult, which is explained by the puzzle being popular among college students and the like. If you don't solve in time, they all drown.
• Uninvited: The Quest for the Red Diamond: The Mall Demon asks you a question regarding intermediate-level mathematics that you have to answer to live.
• In Valkyrie Profile there is an Egyptian-themed pyramid dungeon, in which the Sphinx presents the famous riddle to Lady Valkyrie. Her reply is simply "..." and she is allowed to pass.
• Shows up in the mad Finster's mind in Wasteland; you do have to get these right. Note that this guy's not exactly sane, and the fact that you're wandering in his brain with laser machine guns trying to kill him isn't helping his mental state much.
• In The World Ends with You, on the 4th day of the third week, you are boxed off by invisible walls and to open up these walls, you need to open up special boxes, which won't open unless you solve puzzles involving defeating specific Noise symbols. Additionally, to obtain the Secret Reports, you are required to get hidden items as part of your objectives, and are given cryptic hints as to where to find them, such as "Meet up with the secret" (examine the Statue of Hachikō) and "SHOWN A DREAM" (anagram of "Shadow Ramen," a restaurant where you will find one of the hidden items). Also, some of the clues as to the daily objectives (mostly in week 2) are rather cryptic. Mind you, the characters manage to work them out, saving the player from the extra thought in those cases, at least.
• In X3: Terran Conflict, the New Home plot involves a three-part Hacking Minigame. You have to break a four-digit code, then solve a Sudoku. The third part is inputting a code you put together from clues throughout the plot.

Visual Novels

• Ace Attorney:
  • The series in general is this, with the player either having to find clues, assess evidence, question witnesses or create theories as to how something happened. Only a lawyer (and smart player) is capable of these tasks.
  • In the fourth game, Apollo has to figure out how a professional magician pulled off one of his illusions. Not for any relevant reason, but because The Judge has decided that he wants to know how it was done, and that he wants Apollo to explain it to him. Once he understands, they continue with the actual trial.
• In Danganronpa 2: Goodbye Despair only smart people can play the Final Dead Room's Life-Threatening Game. This is a shout-out to another Spike Chunsoft series...
• Zero Escape is a series of Visual Novels whose gameplay is focused on Escape Rooms, usually under time limits. Characters also tend to be trivia machines, stopping for mini-lectures about science and pseudo-science. Add the fact that the games tend to only use lectures on topics that end up being relevant, it means that all this trivia is actually required to escape. For what may be the crowning example in the series, at one point during Virtue's Last Reward, the only way to begin disarming Dio's bombs, (and thus, ensure everyone lives), is to decipher a code using a key from another ending. This requires that Alice find all the factors of a 25 digit number!

Webcomics

• In Muse Academy, if you're in the dorm for science experts, the door asks newbies science questions, but it's to make sure they're at the right dorm.
• In The Order of the Stick, the Order encounters the classic "one guard always lies, one guard always tells the truth" puzzle on the way to the Oracle of the Sunken Valley in this strip. Haley proves how smart she is by shooting one of the guards in the foot, and determining their nature by their reactions. It's outright defied when Haley returns to the Sunken Valley: the guards seem to remember her, while she doesn't remember them (due to the memory charm put there by the Oracle).
• Subverted in two strips of The Adventures of Dr. McNinja. Turns out, it's not Only Smart People May Pass, it's "Nobody may pass but we were too cheap to get a motion detector or a door." There is no real answer to the riddle; the statue will shoot you if you say anything. It could also be interperted as "No Inocktek may pass", so you're better off not understanding the ancient inscription at all.
  Alt Text: Zelda, I dare you to make a game without this puzzle in it.
• Goblins: These kinds of puzzles are mandatory in any dungeon crawl. Sometimes there is a straight but not always obvious solution, other times the heroes need to Take a Third Option.
  • In Tempts Fate 5 Tempts runs across a sentient door asking him a riddle. An incorrect answer will spell certain doom. So Tempts just opens the door without answering and walks on through.
  • In Tempts Fate 7 there is a series of such puzzles that were needed to be solved by the readers before Tempts could pass them. While all the puzzles were solved, Tempts took a third option on one of them anyway. Tempts Fate 10 is similar.
  • A classic example can be seen here. You have to pull out the tree block, and the real key to the door is literally under it.
• Sluggy Freelance: One of the tests that must be passed to enter the Cave of Yffi (in "The Strombreaker Saga") is a "test of intelligence" that takes the form of a somewhat silly riddle. The heroes make it past by arguing their different answers were all as good as the "right" one. The gatekeeper then tries to make the riddle so specific that it can only be answered the one way ("a bat with lesions"). The villain nevertheless manages to answer it with "a nun with a spear through her head".
• Tower of God:
  • Hansung Yu's door test on the second floor — one of the tests required to advance up the Tower — is an ironic example, because while it can be solved by being smart, it's almost easier by being stupid. The test is ostensibly "Find the right door within ten minutes," and there seem to be no hints. But the implicit hints are all about the time — do it within five minutes — and the real answer is to open any door within five minutes. Thus, overthinking can be much more dangerous than being impatient or impulsive (or even delusional, as with the guy who supposedly uses divination to solve it). Whether Hansung actually thinks this is a reasonable test of determination or whatever like he explains it, or he's just being a sadist with layers of hidden agendas as usual, is anyone's guess.
  • On the Hell Train, one test is to solve a simple numerical riddle to open a door. A group of deadly high-level characters are stumped by this because it's not their kind of thing, but they have a Navigator with them who can solve anything by precognition, although she probably could have solved this one by reasoning too.
• In Wapsi Square Monica meets Phix, keeper of the Bibliothiki, who asks her a riddle. When Monica answers, Phix gives her a prize. Later on Monica takes her friend Shelly to meet Phix, who asks her the same riddle [large-format strip]. The twist is that Shelly gives her a different answer but also gets a prize. Note that Phix doesn't say that either of the answers are right, she just says "good for you".
• In War and Peas, a knight saves a girl from multivariable calculus lessons, then... see the page image.
• xkcd:
  • The Knights and Knaves puzzle is played for laughs in this strip.
    And here we have the labyrinth guards. One always lies, one always tells the truth, and one stabs people who ask tricky questions.
  • Conversed in this installment, where it's noted that characters in stories often use riddles to communicate key messages.

Web Original

• In The Tim Tebow CFL Chronicles, the Toronto Argonauts find an empty aircraft carrier waiting for them. The only instructions on how to operate the ship are a plaque in the bridge with a strange shape and numbers inside it. Tim Tebow immediately recognizes the plaque as a cryptic reference to a specific football game: November 13, 2011, Denver Broncos vs. Kansas City Chiefs. Tebow was the Broncos' quarterback for that game, and he realizes this is a clue to use several stats from the game to determine how to start the ship's engine and set the bearings.

Western Animation

• Elena of Avalor: When the new (and largely untrained) royal wizard Mateo needs to access a powerful spell book in order to reverse a curse, he discovers that the spell book can only be found by solving several riddles. The trope is then played with when it turns out Mateo can't solve the riddles and begins to question if he should be the wizard at all; Elena then insists that it's fine if he relies on his friends to solve the puzzles as long as Mateo gets the spellbook and saves the cursed people in the end.
• He-Man and the Masters of the Universe (1983): In "The Secret of Grayskull", Castle Grayskull will let in anyone who answers a riddle. When Skeletor and his minions tried to gain entry, it asked, "What goes through a door, but never enters or exits the castle?" The bad guys couldn't figure it out, so they asked a brainwashed Orko whom they had captured, who answered a keyhole. Likely due to the Sorceress realizing what a security risk it is, Grayskull doesn't ask riddles in future episodes.
• Played with in Phineas and Ferb Arthurian Legend-slash-The Princess Bride-slash-The Lord of the Rings episode "Excaliferb" has Professor Poofenplotz as a bridge-guarding troll who demands that the answers to three questions must be given correctly in haiku form in order to pass. Baljeetolas notices that the creek is shallow, and the questers go around the bridge, although Baljeetolas gives the correct answer after crossing the creek. Just for the hell of it. Later in the episode, Candavere approaches the bridge having transformed into a uniwhalescorpiopegasquidicorn... girl. Poofenplotz lets her pass out of fear.
• VeggieTales did an Affectionate Parody of The Lord of the Rings, which has a scene similar to the Gates of Moria. As the show is for kids the riddle is quite easy. The answer is an elephant.

Real Life

• High IQ Societies, like MENSA, require an IQ of at least 130 to join. Either that or a certain percentile on a standardized IQ test, since the absolute score tends to vary between different tests.
• This is the point of the technical interview for information technology jobs. The interviewers will give you programming-related logic puzzles to solve and they consider how you attempt to solve these relatively basic problems to assess how well you might handle more complex coding work. This has changed as time as passed. A lot of the "standard" questions have been spoiled by now, so it's effectively becomes a test whether you're clever enough to use Google to prepare beforehand or not. In a lot of real world situations, reinventing the wheel is a bad thing. Figuring out that someone else has probably already solved the problem and finding and using their solution is likely to be a lot faster than working it out yourself, making it a decent screening test again, if not for the reason the interviewer intends. This technique is falling more and more out of favor with both interviewers and interviewees, however, and is generally being replaced with straightforward written tests. How a candidate evaluates a given problem and writes some code to solve it is a more concrete indicator of that person's potential performance on the job than being able to come up with (or just remember) some clever answer to an abstract thought exercise.
• Academics naturally has a lot of these. The purpose of an exam is to prove that you are smart enough to advance to the next level.
  • Graduate school oral exams (and, to a lesser extent, the dissertation defense) are this since the committee can, theoretically, ask you anything related to the subject in question.
  • For those studying to be a lawyer:
    • The Law School Admissions Test, or LSAT, in the United States is an imposing 3.5 hour challenge which tests logic, critical thinking, reading comprehension, composition, and more under a very strict time limit. The test-takers generally are college seniors and grads with good enough grades to fancy they will attend law school. Many prepare for weeks to months for the exam, and yet fully half of test takers will not score well enough for them to enter even the lowest tier law schools in the United States.
    • Pass this challenge, and the bar exam awaits, a test which often is more than a full day long. A law student in theory studies for three years for it, and some take time off after law school to further prepare for the exam. There is no single "bar" exam. States determine the requisite for their own bar exams, but a day of questions and a day of essays is the norm.
  • For those studying to be a doctor:
    • Doing well on the 7.5 hour-long MCAT (Medical Colleges Admission's Test) in the United States requires extensive knowledge of biology, physics, chemistry, and organic chemistry as well as excellent reasoning, reading, and composition skills. Everyone taking the exam has or is finishing up a college degree, most of them in biology or chemistry. Furthermore, many students study for months to prepare and have to self-select for being competitive students so a med school will admit them. Two-thirds of the test-takers will not get into med school.
    • An aspiring American physician can then look forward to the United Steps Medical Licensing Examinations - plural - colloquially known as the "boards." There are four full-day (or two-day!) exams, called Step 1, Step 2 Clinical Knowledge, Step 2 Clinical Skills, and Step 3 that must be taken. After clearing these hurdles, boards for each specialty a physician wants to certify in still have to be taken.
  • While the US' exams are the most well-known due to Eagleland Osmosis, frankly the path to these careers is littered with similar challenges in any nation where corruption hasn't become too big a part of the system.
  • In the United States Armed Forces, most people can score well enough on the Armed Services Vocational Aptitude Battery Test to enter the military. Low performers will be limited to low-skill jobs such as truck driving; it takes a fair amount of intelligence for a person to do well enough to be considered for higher-skill jobs such as pilot, linguist, or medical, and the training for many technical jobs have a surprisingly high wash-out rate from those who intellectually can't hack it.
• Certain companies make the clever choice to not leave their contact information out in the open, but instead hidden behind multiple clicks that you will only know to click, if you have at least average intelligence. That saves the companies from hundreds of really dumb emails, and ensures that the ones that do get in, are mostly on-topic.
• The community forums for Adventure Game Studio, a tool for creating Point-And-Click Adventure Games, requires new registrants to answer a series of questions on proper etiquette. The questions are all multiple choice and the correct answers are incredibly obvious, in context, but framing the rules as a quiz forces users to read them and pay attention to them, rather than just clicking past them.
• This is the whole concept behind escape rooms, a popular form of entertainment that originated in Japan and spread all over the world. Based on the You Wake Up in a Room genre of video game, escape rooms see players "trapped" in a small area for one hour, and they are required to solve puzzles, find hidden objects, and use the items they acquire to complete a goal—often escaping, but sometimes other tasks like collecting a hidden treasure or catching a criminal. Some games lack any sort of story and simply have players completing puzzles for no reason, while others have more involved plots that justify each challenge. While the games are often advertised as tools for team building and communication, they're primarily tests of intelligence and the ability to think creatively. Notably, it's considered bad design to include Only the Knowledgable May Pass in escape rooms—everything required to win should be included in the room, and needing outside or specialized knowledge to succeed is a quick way to irritate customers.

---