It's mainly about the guard of c3+c4 by LIc6, and the guard of d3+e4 by LIg6. The lions can switch…
Right! On my board, a black Bishop c6 was missing.
Perhaps I wasn't clear: Mirroring the position doesn't work, because Kjell's dual would still work: 1. a4xBb5->b2 Bc6-b5+ 2. Ke3-d3…
It isn't possible 1.Qd4+ as s=1, because Black has 1. ...Kc6!
No, because 1. Qd4 Bxd4[Bc8] is also possible as s=1. Perhaps +wPa6.
Could this be fixed by mirroring the position vertically?
I couldn't have explained the contents better - so thank you very much, Kjell!
Quite economical and beautiful K-chase with a draw pendulum at the end, with the traditional trick of an en-passant capture…
Isn't this cooked (dualized) by (1.h4xBg5>g2 Bf6-g5+) 2.Kd3-e3 Ba8-e4+ (to cancel checks from Be4, Rc3, and Rh3) 3.Ke3-d3 & forwards…
The logic is not as simple as one would think (which makes the problem all the more interesting). The Breton…