Good old times 15

1.Rd5? th. 2.Qxe4,Qxc3,Qxc5#
1...Nxg3!

1.Nh4! th. 2.Ng2#
1...Rd5 2.Qxe4#
1...Bd5 2.Qxc3#
1...Nd5 2.Qxc5#
(1...e1S,e1N 2.Sd1#
1...Gf3 2.Qxe2#)

Aggressive try with triple Novotny fails , therefore White creates different threat and waits for black triple Grimshaw. Note that moves of black trio RBN not only creates mutual intereferences, but also unpins wQ. There is also cyclic dual avoidance yielding a good cyclic impression.

1.Ke8! th. 2.Qxd3(d7)+ Sxd3(Qd1) 3.Qxd3(Sg8)#
1...Sd2 2.Qxd2(Sb8)! th. 3.Qb4#, Qc3#,
      2...Bxd2(Qd1), Sxc2(Rh1), exd2(Qd1) 3.Qxg4(Ra8)#, Qxd3(d7)#, Bf2#
1...Bd2 2.Qxd2(Bf8)! th. 3.Qb4#, Qc3#,
      2...Sxd2(Qd1), Sxc2(Rh1), exd2(Qd1) 3.Qxa1(Rh8)#, Qxd3(d7)#, Bf2#
1...d2 2.Qe2! th. 3.Qc4#, Rc4#,
      2...Sxc2(Rh1), Sxe5, Sd3 3.Qd3#, Bxe5(Sb8)#, Qxd3(Sg8)#

In the key wK avoids selfcheck by reborn wS and thus creates an easy Circe threat.

Then interferences on d2 are met by captures by queen and White piece eat their way to the black king. They use well the rebirth possibilities, especially the queen.

1.h8S! h3 2.Sg6 hxg6 3.Sd7 g5 4.b8Q g4 5.Qe8 g3 6.e7 g2 7.Qh6 gxh6 8.f6 h5 9.f7 h4 10.f8Q h3 11.Sc7 Rxe8 12.Sa8 R~ 13.e8B#

With bK safely locked on c4 it suffices to promote wP into light-squared bishop. But it is not so easy. Advancing the only wP available for this plan, Pe6, would allow defence Kxe7. Therefore White has to block e8 with promoted queen. Why queen? Due to lack of moves, White has to sacrifice promoted knight quickly on g6 and later also Qe3 which has to be replaced by her colleague to hold d-file. Finally, to allow safe unblocking of e8 white has to use Mars powers of Rh1 who cleans e8 for him. That is why another queen has to appear.

Impressive scenario.

1.Qg8! - not mate.

The rare stipulation asks for finding the single white move that does not checkmate Black immediately. It is 1.Qg8, but the main point of the constructional exercise is in the arrangement of as many checkmating moves as possible. 32 seemed to be a record in 1990 when the issue 96 of feenschach was published and it might still hold today.

1.fxg6 e.p.! - not mate.

One more position with all legal white moves checkmating Black, except one. Here the idea is to show the least visible move as the one, as only small retrograde analysis shows the e.p. capture is the solution.