# Checkmate all the kings #3

Following the rules created by Lord of dark in this puzzle, and used here also, the idea is to find the minimum number of consecutive white moves to checkmate all the black kings (in this case 12). You cannot make a move that would put white in check.

RULES

• You are playing as White and you can make as many moves as you want before Black's turn.
• During your moves you can take any black piece except kings.
• During your moves your king can not be in check position.
• At the end of your turn all the black kings must be check mate : if Black can make one move that ends with one king being safe, you don't win. Note that this one move can't be a king moving to a threatened position.
• One piece can be used in multiple checkmates (you don't have to take all the king, just to checkmate them)
• How do you get pieces to promote properly with that interactive board? I just tried it, and a promoted pawn can move like a queen but still looks like a pawn. Mar 18, 2017 at 17:09
• It's a bit manual! You just need to drag a queen onto it - it's two interactions. Flexibility vs convenience trade-off... Mar 18, 2017 at 17:10
• I make my animations by opening the link on my phone and taking screen shots there... Mar 18, 2017 at 17:11
• @randal'thor Actually, you can drag the pawn anywhere... Mar 18, 2017 at 22:08

Thirteen moves:

1. d x c8

2. c x d8

3. h x g8

4. g x h8

5. Q x b6

6. Qc x c5

7. Q x c4

8. Q x c1

9. Qc x b2

10. Qg2

11. Qg x b7

12. Qh3

13. Qh x b3

Here's an animated GIF of the solution. (Assume all promoted pawns become queens, since I couldn't figure out how to convert them automatically using this particular chess software.)

• This doesn't checkmate all the kings: black can take a queen (any of them) with one of the knights, after which some kings will no longer be in check.
– hvd
Mar 18, 2017 at 18:20

I've done it in 18 moves, one pawn at a time:

Solution:

Moves:

H pawn:

1. hxg8=N, Nf6, Ne4, Nc3

G pawn:

5. gxf8, Ne6, Nd4, Nc2

C pawn:

9. cxd8, Nc6

F pawn:

11. Fxe8, Nf6, Nfd5

E pawn:

14. e8=N, Nc7

D pawn:

16. d8=N, Nde6, Ned4

• This was more what I was aiming for, but the queens do a better job. Mar 22, 2017 at 22:52

Found it in 11, probably the optimal.

C pawn takes D8 and B6 - 2 moves

.

D pawn takes C8 and B7 - 2 moves

.

E pawn takes F8 and C5. Then waits a bit. - 2 moves

.

F pawn takes G1, C4 and B3. - 3 moves

.

E pawn now takes C1 and B2. - 2 moves

• Eight knights need to be captured, four pawns need to promote, and only one knight is on the last rank, so you can't do better than 11 moves. Mar 8, 2021 at 4:37