[Challenging and Fun!] Quizzes & Riddles for Adults
We’re introducing riddles and fun quizzes for adults!
When you hear “riddles” and “quiz questions,” you might think they’re for kids, but these days there are quiz shows that adults can enjoy too, making them fun for all ages.
In this article, we’ve put together some slightly challenging riddles and quizzes for adults.
They’re especially recommended for grown-ups, whose thinking can sometimes get a bit rigid!
Try them as brain training, too.
You might be surprised by how difficult they are!
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[Challenging and Fun!] Quizzes & Riddles for Adults (41–50)
A super difficult problem with two possible answers
This is an ultra-difficult quiz with two possible answers.
The questions are designed so that if you follow a certain rule, two answers emerge.
These quizzes demand flexible thinking—considering what numbers written in katakana might mean, or combining symbols with something else to fit a condition.
The key is to avoid fixed ideas and approach the answers from various angles, such as numbers, kanji, and symbols.
Start with practice problems and gradually increase the difficulty to enjoy the challenge.
These quizzes can also be used in full-fledged quiz competitions—for example, by providing respondents with paper and pens or allowing longer thinking time.
[Challenging and Fun!] Quizzes & Riddles for Adults (51–60)
Caesar Cipher Quiz
This is a quiz that uses the Caesar cipher, which creates a code by shifting letters by a fixed number.
For example, if you shift “WORLD” forward by 3 letters, it becomes “ZRUOG.” Even if a word looks meaningless at first glance, the key point is that you can reveal the original word by shifting back using the same rule.
To decode it, you need careful observation and patience to determine the correct shift amount, but the sense of accomplishment when you grasp the pattern can be addictive.
It’s perfect as brain training for adults, since you can have fun while honing logical thinking.
Once you get used to it, you can also encrypt your favorite words yourself and exchange them with friends, making it a quiz with a wide range of ways to enjoy.
A cipher riddle quiz using kanji
The combination of kanji and ciphers is a puzzle packed with brain-training elements that make the most of the depth of Japanese.
You’re given the reading of three kanji characters as a hint, and the challenge lies in how to use it.
It’s a riddle where you search for clues from a lined-up string of kanji.
Sometimes romaji serves as a hint, and answering while considering meanings tests your mental flexibility.
Simply knowing kanji isn’t enough—you need creativity and a shift in perspective, which is part of the appeal.
It’s a puzzle that lets you experience the fun of looking at kanji from an unusual angle.
A cipher quiz using mathematical formulas
A cryptic quiz that looks like simple addition but uses completely different logic to reach the answer.
Equations that seem nonsensical—like 3+7=“trauma” or 4+6+2=“sea slug”—hide tricks such as the ordering of letters or words.
It’s recommended to consider the problem from multiple angles, including letter order and wordplay.
Finding the answer tests your ability to think outside the box.
It’s not just about logical reasoning; a feel for language is also required, making it a quiz that gets your whole brain firing—and becomes addictive.
Answer the animal from the number code
This is a brain-teaser quiz where you deduce the name of a specific animal from what looks like a random string of numbers.
There are conditions like 11555 = dog, and you figure out the correct answer by using the hints hidden in the numbers.
As you solve the puzzles, you consider whether there’s a cipher rule and what the numbers mean in relation to the animal types, so flexible, outside-the-box thinking is required.
The key is to look at the problem from multiple angles.
Familiar numbers line up like puzzle pieces, creating a mystery that’s so engaging even adults will get hooked.
Quiz to find the hidden letters in the cipher
How many of these can you solve? “The Hidden Letters in Codes Quiz” is a seven-question intellectual challenge that unravels mysteries concealed in familiar words, kanji, and English spellings.
By interpreting characters from a different perspective than usual, you’ll arrive at surprising answers that make you think, “Aha!” These problems call for flexible thinking and flashes of insight, making them perfect for a mental workout or a quick refresh.
It’s an ideal, easy-to-try intellectual pastime for adults, suited to brief moments during commutes or breaks.
World Automaker Logo and Emblem Quiz
Here’s a common difference in how things are called by foreigners: what we in Japan call “Benz” is known as “Mercedes” abroad.
It seems that’s because not everything called “Benz” is the same “Benz.” Maybe it’s similar to calling all Japanese video games “Nintendo”? For car lovers, don’t miss this “Logo & Emblem Quiz.” You might recognize the big names like Mercedes, Ferrari, and Lamborghini, but once it gets a bit more obscure… Gather your car-enthusiast friends and have a blast with this quiz!