Unbelievable to me

I find it amazing that you can prove what piece it is.

By Alexander Yarosh. The position above was reached in a legal game, except that one piece has been knocked off the board. What was it?

ack’s pawns have made 14 captures altogether, which accounts for every one of the missing white pieces. So the missing piece cannot be white. Both kings are in check, which is illegal, so the missing black piece must be on a2, blocking the rook’s check. The missing piece cannot be a queen or rook, as this would put the white king in an illegal double check. So it’s a black knight or a black bishop. And it can’t be a bishop — Black’s light-squared bishop never left its home square (the pawns on b7 and d7 have not moved), and all his pawns are still on the board, so Black has made no promotions. So the missing piece is a black knight on a2.

From Schachmatnaja komposizija, 2007. Answer above in white

That one is really easy! A little bit of reasoning and counting should get you to the answer quickly.

The most famous "knock off" problem is the one in Smullyans book where you must place the missing king on the board. I assume you know it. It is magnificent!

 No  I don't know it,I posted a problem from the cover of his book that I took from another site,I don't have the book.I have actually just started being interested in chess in the last six months have not read any books about it.I read what the rules were and started doing these puzzles which I am getting addicted to....I have to admit I looked at it and thought impossible without really trying.If you still have it could you post it here.I will keep it and keep trying to solve until I get it.

I thought the next problem was on the cover of Smullyan's Sherlock Holmes book but I may be mistaken. It's decades ago I had a peek in it.

Add the wK to the diagram such that it is legal!

  You could have had a different edition then they had,they change covers all the time. I have to place the king and the reasoning of why it is there to solve this.Lol it is going to take some time for me.  The guys playing left the room in a huff for some emergency knocked the white king off the board  you pick it up and accuratly place the king back on the board you don't know whose move it is even but, you will if you solve it.  You may laugh but this is  going to be a project for me.   BTW what did you think of that other two mover I posted last night.

Not sure which one you mean. All the other twomovers are older and I commented on most of them. Edit: Just found it! I'll take a look.

Edit: Sam Loyd was the best composer in his time. He won a bet with a friend that he could compose faster than his friend could solve. Incredible! This one is not difficult for me but it has good content for a miniature twomover!

As I've previously seen the problem with the missing White king, I won't spoil anything here. Instead, I'll share a related construction challenge I came up with a few years ago. Alas, I did not have the experience with such things back then that I do now, so the "challenge" is far too easy to be taken seriously. I won't try making it harder though, since the puzzles in this thread are seemingly intended to be very much on the easy side, anyways.

Devise a position in which all of the following statements can be proven:

• If there are no missing pieces, then the result will be a draw with best play, regardless of whose move it is.
• If there is a missing Black piece, then the result will be a win for White with best play, regardless of whose move it is.
• If there is a missing White piece, then the result will be a win for Black with best play, regardless of whose move it is.

  @ cobra91 This type of puzzle is not easy for me,don't wait up for an answer.I appreciate the input though.I will give it a try.

Since it doesn't look like anyone will bother with my construction challenge (can hardly blame them, as without improvements it was totally unworthy of solvers'/composers' attention), I shall post my 3 solutions from a few years ago (back when I first thought of the idea). Despite how little experience I had at the time, I did at least succeed in demonstrating the most trivial ways to complete the task:

in the first one why do you lose if you have a queen on the board?

Thank you for the comment (or question, technically)!  

Fortunately, it's not hard to prove there is no queen on the board. Not even an "invisible" queen... which was the main point of the idea.

Nice examples! The next step is to do something asymmetrical. Another next step is to have at least 2 different legal additions, losing in different ways (for instance after adding a rook on a1 or b1).

I wanted to give this a try but I misunderstood the phrase "if a piece is missing ..." so I let it go. My mind reasoned: "if the position is a draw, then how could something be missing?" In Smullyans diagram, the king is actually missing. Not to say your wording is wrong but to avoid confusion you might wish to state it in another way:

... (a) the position is a draw (b) if you add any white unit, black wins (c) if you add any black unit, white wins [whoever is on move in all cases]

Btw, I can't meet all your challenges, there are some in real life as well

@ cobra91  You will get a laugh but to me, "if there are no missing pieces" means there are 32 pieces on the board.I have no expierience with these except from these few posts.even if I knew the challenge correctly I would have never came up with the solution that I see here.

The missing piece is black knight at a2...

reason of thinking is as follows:

1. who made last move ?

2. Both kings are at Check ....cannot be

3.All positions of black king are check so it means that the king didn't come from any other position.

4. The white rock could not have been next to the Black king , so the rock did not move...not logical.

5. The White King will not move into check ...also not logical.

6. So the last move into this position was made by the Black...which means king could not have been checked ....hence the missing piece is at A2.

7. It could not have been a pawn ...cannot logically accumulate all that number of pawns in one column.

8. Cannot be a queen or rock as the white king would  not move into check.

9. Thinking back words the move before it could not have been a white bishop as where posibly was the white king before that ...

10 My conclusion is a black Knight.

11 . It also protects the pawn above the black king.

12. Black won.

 Dear Arisktotle ... are you sure that this missing white king has a solution, I find it impossible to be real...

If there a solution just insure it for me as it sounds impossible to reach this situation at all...

if I am wrong....just another one in my bucket of mistakes.

@Hajafar: It's one of those problems you want to bet against a millionaire. Let him look at it for a week until he is sure it can't be done. Then bet your wife for his millions that a perfectly regular solution exists. You'll end up rich, my guarantee!

Accepted....but won't tell my wife.

  LOL Hajafar please post in white if you get the answer I said I am not giving up on this one (wish I didn't say that)@ Aristotle did you get the solution to this one the first time you seen it?

Frankly I don't remember, too long ago!