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Albert.Lang
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Nicer picture (thanks @justhalf !)

enter image description here

Nicer picture (thanks @justhalf !)

enter image description here

Source Link
Albert.Lang
  • 6.3k
  • 11
  • 43

With the new hints this has become much simpler. In fact, OP has (unintentionally?) changed the character of the puzzle. At least some solutions can be step-by-step (like a sudoku for want of a better simile) reconstructed from the hints.

For example number 8 (I'll only do one, so people still have a chance to earn the bounty by solving one of the others):

Let us assume that in each non rectangular area every convex corner not touching the boundary is actually occupied and see how far we can get:

   8   . b b b b b b .
   7   . b b b b b b .
   6   W!. . . . . . .
   5   w . . . . . . B!
   4   w w w W!. B!b b
   3   w w w w W!b b b
   2   w w w w w B!b b
   1   w w w w w W!. B!

       a b c d e f g h

   w: white piece or empty   .: empty    W! white piece
   b: black piece or empty               B! black piece
 

Because of the white pieces on f1 and e3 the black piece on f2 can only be a N. As this N attacks h1 the h3 and g4 squares must be empty. Similarly, f4 must also be a black N and g2 empty. On h1 there cannot be a R or Q because of the white piece on f1. Black Ns are used up leaving a K or a B. But if h1 were a K h2 would have to be a B (the K has to attack something, and that something must not attack him back) but that would leave the N on f2 unreachable. Therefore h1 is a B, f3 is empty and there is a black piece on b7.

   8   . b b b b b b .
   7   . B!b b b b b .
   6   W!. . . . . . .
   5   w . . . . . . B!
   4   w w w W!. bN. b
   3   w w w w W!. b .
   2   w w w w w bN. b
   1   w w w w w W!. bB

       a b c d e f g h
 

Of the black pieces still available only a R can sit on b7 without attacking the white piece on a6. The only way of attacking the knight on f2 without also attacking f4 or h5 or h1 is a B on h4. As the only piece that can attack the Q is a N and the f2 N already attacks another piece h5 must be the Q. To close the cycle g7 must be the K and f8 the other R.

With the black chain complete we can remove the remaining black markers and also all the white ones that are attacked by black pieces:

   8   . . . . . bR. .
   7   . bR. . . . bK.
   6   W!. . . . . . .
   5   . . . . . . . bQ
   4   w . w W!. bN. bB
   3   w . w . W!. . .
   2   w . w w . bN. .
   1   w . w . w W!. bB

       a b c d e f g h
 

The piece on a6 cannot attack b7 ruling out Q,B,K nor can it be a N because there is no suitable white target, so it must be a R. This R can only be attacked via the a6-f1 diagonal. As there is piece on f1 a Q or B between a6 and f1 would attack at least two pieces. Therefore f1 must be the B and the rest of the diagonal empty.

   8   . . . . . bR. .
   7   . bR. . . . bK.
   6   wR. . . . . . .
   5   . . . . . . . bQ
   4   w . . W!. bN. bB
   3   w . w . W!. . .
   2   w . w w . bN. .
   1   w . w . w wB. bB

       a b c d e f g h
 

Of the squares left the only one where the Q doesn't attack two or more other pieces is c2. To shield the black Nf2 there must be another white piece on d2 which in turn forces a2,a4,c1,c3 to be empty.

   8   . . . . . bR. .
   7   . bR. . . . bK.
   6   wR. . . . . . .
   5   . . . . . . . bQ
   4   . . . W!. bN. bB
   3   w . . . W!. . .
   2   . . wQW!. bN. .
   1   w . . . w wB. bB

       a b c d e f g h
 

Only one of the a1 and a3 squares can be occupied. Indeed, a3 would have to be a N and a1 a N or B. They cannot both be Ns and B on a1 could only be reached by a R on e1 which would also attack f1 and e3.

With only one more square useable in the a-file e1 must be occupied. This leaves a1 as the only possible square for the dark-squared B, d4 as the only place for the K and e3 as the only place for the remaining R. The Ns go to d2 and e1.

Fully reconstructed position:

   8   . . . . . bR. .
   7   . bR. . . . bK.
   6   wR. . . . . . .
   5   . . . . . . . bQ
   4   . . . wK. bN. bB
   3   . . . . wR. . .
   2   . . wQwN. bN. .
   1   wB. . . wNwB. bB

       a b c d e f g h