Funny problems with discovered checks (easy for engines and surely easy for people).

[Ajedrecista]

Hello:

I come with an idea that is probably not new, but which I have not found in a brief search: it consists of giving a series of discovered checks until the checkmate (or almost), or to have a winning position, starting with a heavy material disadvantage. We all can produce thousands of such positions like 5K1k/b6b/6P1/8/4q2r/3qq2r/2qqq2n/1qqq3n w - - 0 1 (g7# in K+P versus K+9Q+2R+2B+2N). However, I bring some positions that I composed in good moments (there can be more with different subtleties).

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The first one is more straightforward, with discovered checks here and there until it the moment of giving checkmate arrives:

[pgn][Event ""]
[Site ""]
[Date "2025.04.01"]
[White ""]
[Black ""]
[SetUp "1"]
[FEN "4R1b1/4RBbk/4r1pp/3n3p/2n4K/1r6/q7/8 w - - 0 1"]

1.Bxg8+ Kh8 2.Bxe6+ Kh7 (2. ... Bf8 3.Rxf8#) 3.Bg8+ Kh8 4.Bxd5+ Kh7 5.Bg8+ Kh8 6.Bxc4+ Kh7 7.Bg8+ Kh8 8.Bxb3+ Kh7 9.Bxa2 g5+ 10.Kxh5 g4 11.Bb1# 1-0[/pgn]

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The second one is a bit more elaborated, with a tempting avoid move at some point only adding two pawns, one of each colour:

[pgn][Event ""]
[Site ""]
[Date "2025.04.01"]
[White ""]
[Black ""]
[SetUp "1"]
[FEN "4R1b1/4RBbk/4r1pp/3n3p/2n3pK/1r4P1/q7/8 w - - 0 1"]

1.Bxg8+ Kh8 2.Bxe6+ Kh7 3.Bg8+ Kh8 4.Bxd5+ Kh7 5.Bg8+ Kh8 6.Bxc4+ Kh7 7.Bg8+ Kh8 8.Bxb3+ Kh7 9.Rxg7+ (9.Bxa2 g5+ Kxh5 1/2-1/2) Kxg7 10.Bxa2 {White wins.} 1-0[/pgn]

It should be a checkmate in 23 moves from the starting position.

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The third one is a variation of the first one, adding one black passed pawn that threatens queening and initially blocks the checkmating diagonal:

[pgn][Event ""]
[Site ""]
[Date "2025.04.02"]
[White ""]
[Black ""]
[SetUp "1"]
[FEN "4R1b1/4RBbk/4r1pp/3n3p/2n4K/1r1p4/q7/8 w - - 0 1"]

1.Bxg8+ Kh8 2.Bxe6+ Kh7 3.Bg8+ Kh8 4.Bxd5+ Kh7 5.Bg8+ Kh8 6.Bxc4+ Kh7 7.Bg8+ Kh8 8.Bxb3+ Kh7 9.Bxa2 d2 10.Bb3 {Checkmate soon.} 1-0[/pgn]

It should be a checkmate in 13 moves from the starting position.

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There can be many more variations: for example placing other pawns, knights, rooks (neither bishops nor queens) or nothing to b3, c4 (depending, not a rook if it gives check to the white king), d5 and e6 squares; replacing the black queen on a2 with other black piece; putting a black piece (except a pawn) or not on g8; adding some pawns elsewhere to add subtleties to the main idea of the first position; and so on.

If you try them by yourselves, do not get fooled by the stalemate carelessness in the second problem!

Regards from Spain.

Ajedrecista.