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The Eight Queens Puzzle is one of the most famous chess problems of all time. The premise is simple- place 8 queens on a chessboard so that none of them attack each other. A solution is shown here:

enter image description here

Here's a separate challenge- instead of using queens, you can use any piece! Pieces have their point value as normal:

Pawn: 1

Knight: 3

Bishop: 3

Rook: 5

Queen: 9

You have to place exactly 24 points of pieces so that none of them attack each other BUT... there's one other rule!

For every possible legal move in the position, after that move is made, no pieces are attacking each other.

For example:

enter image description here

This is a legal 7-point solution- none of White's legal moves result in any pieces attacking each other.

Your job is to find a 24-point solution.

I believe there are 5 unique solutions not counting reflection. The more solutions found, the better! Check mark goes to first to find all 5.

Note: The normal piece limits don't apply, so 24 could be made up of 3 rooks and 9 pawns, or anything of the sort.

Pawns can promote, and you can't put them on the 8th rank to start.

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    $\begingroup$ Are the pieces all to be of the same colour? (It matters because it affects what legal moves they have.) $\endgroup$
    – Gareth McCaughan ♦
    Commented Nov 6, 2018 at 18:42
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    $\begingroup$ @GarethMcCaughan yes. $\endgroup$
    – Excited Raichu
    Commented Nov 6, 2018 at 18:43

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Well, this here

enter image description here

seems to work.

Rearranging the columns, you can get two more solutions.

EDITED:

I'm not really sure how many symmetrical positions there are in here, but if you remove any 4 pieces from this 36 point pattern, you should get a valid solution for the 24 points. (You can also flip some of the corner clusters and repeat the process to find some more solutions.)

enter image description here

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    $\begingroup$ Yup, that's one of 'em. $\endgroup$
    – Excited Raichu
    Commented Nov 6, 2018 at 18:27
  • $\begingroup$ Well, I definitely missed that, lol. My original 5 solutions were the three pawn ones, the 36 pointer without the knights on b8, g8, b1, and g1, and knights on a6, c8, f8, h6, h3, f1, c1, and a3. This does have (at least) 5 solutions, though, so I'll give it the check. $\endgroup$
    – Excited Raichu
    Commented Nov 6, 2018 at 18:53
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    $\begingroup$ A pretty comical pawnstack there! +1! $\endgroup$
    – Tzu Li
    Commented Mar 7, 2019 at 3:57

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