Similar to: Unlucky tiling: Arrange thirteen right isosceles triangles into a square Five graded difficulty isosceles right triangle into square tilings Each tiling has only one solution, these might be possible by hand, computers allowed. The two challenges are to arrange $17$ right isosceles...

One day, a man was hunting. When he saw an animal, he fired his gun. Realizing his mistake, he had a few seconds to run, but was soon dead. What happened?

prime number off blue additions STOP IMMEDIATELY! DANGER AHEAD! I look a bit danish just give me a tug

Each of the clues below gives two words. In each case, those two words share a certain relationship; that relationship in turn gives you a single letter. The 17 resulting letters spell out two final words. To verify that you have the right two words, they will have the same relationship that a...

I mean, can I use it to hide an answer from my question or a hidden hint? Of course without showing it on the post. There're people use this method. I've been looking for this but got nothing. Sorry if duplicate. Thanks.

Given a square piece of paper (say 1x1), what is the largest cube net you can cut out of it? ('largest' meaning with maximal area; 'net' meaning it's possible to fold into a cube (somehow)) This puzzle was stolen from 'The bedside book of geometry' (Mike Askew and Sheila Ebbutt) which I hap...

You disable the security shields. Dr E releases his minions. Suddenly you hear the red siren. 'Code-Red' says the computer. You smell smoke. You see the background a blur and noises in the air. Your passing out. It seems you are dead........ You bang your head into the nearby wall. "This is...

Similar: Unlucky tiling: Arrange thirteen right isosceles triangles into a square Five graded difficulty isosceles right triangle into square tilings Two difficult "Seventeen right isosceles triangles into a square" tilings The challenge is to fit the smallest $20$ integer-sided scaled right i...

1. Early scientists see major progress. 2. Gray scale picture subject? 3. Midas tunes up this hangman cheat. 4. Endlessly in Whiterun; Croesus is the key. 5. Shuffle mode of 4? 6. With a minor change, sounds like garlic mayo. 7. Made successive notes in his ancient Opus. Bonus ...

When I am in the sea, I'm always falsy When you add it, you can finally see me ! When you take a drink with me, people say I'm foolish - but I always drop the l. hint:

Although fuzzy, you don't want to pet me. A force of nature holds me together. I grow, but I'm not alive. What am I?

What lives on the bottom of four legs Left there by one to stay Never to come out Until... What am I?

What book am I? I am old, old, old... On a subject that nobody reads... Popular according to Google... Wrote by a zoologist. What book am I?

This question is part of the best-puzzle award series. What are your nominations for the best puzzles, here on Puzzling.SE, of the fourth quarter (October/ November / December 2017? Suggested guidelines for nomination: Nominate each individual puzzle in a separate answer, so they can be...

This question is part of the best-puzzle award series. What are your nominations for the best puzzles, here on Puzzling.SE, of the first quarter (January/ February / March ) 2018? Suggested guidelines for nomination: Nominate each individual puzzle in a separate answer, so they can be u...

I am you, you are me. I see you and you see me. I friend I am, a enemy too. Slayer of gods, murdered me too. I kill you now, hunt you never. Clash with your head, kill your tether. Who am I?

My prefix is a trusted mate. My suffix, cause for neighbors' hate. My infix is a cheerful youth. My whole is a powerful servant of truth.

TWO came forth from the very same mother and most people could not tell one from the other They arrived the same day, on the very same spot, they look just the same, yet twins they are not To further explain this perhaps I should say that one of these two was given away In fact both were wanted,...

My prefix is sufficient, just meeting expectation. My infix is a call to arms that condemns hesitation. My suffix is a next of kin, a term that's so endeared. My whole, I think, will leave you stunned, a status to be feared.

There are five bags of gold that all look identical, and each has ten gold pieces in it. One of the five bags has fake gold in it. The real gold, fake gold, and all five bags are identical in every way, except the pieces of fake gold each weigh 1.1 grams, and the real gold pieces each weigh 1 gra...

I kill none. I slay all. I eat those who have none. I must be honest, you will die. To my claws, you reach nigh. Who am I?

I found this riddle and answers in the link Turn off all lights in a ring-shaped palace, and people ask me if there are anyway to do also the number of the rooms in linear time, there are anyway to do it?