Queen promotions 6

a)
1.Rb3! th. 2.Ra8#
1...Rf3! a 2.f8Q# A
1...Rf4 b 2.Qxd7# B
1...Re3! c 2.e8Q# C
1...Re4 d 2.Rxc7# D
1...Qxa3 2.Qg8#

b)
1.Rb4! th. 2.Ra8#
1...Rf3 a 2.Qxd7# B
1...Rf4! b 2.f8Q# A
1...Re3 c 2.Rxc7# D
1...Re4! d 2.e8Q# C

After keys any move of Rf5 allows Qxd7# and any move of Re5 allows Rxc7#. Then precise moves to 3rd and 4th rank are reciprocally of "any" character and corrections. After correction, there is a flight b8 because of paralysed wR, but bR is paralysed as well and the queen promotions follow. Nice mechanism!

1.c4+? Kb4!

1.Rd5+? Kc4!

1.g7! th. 2.g8Q ~ 3.Qe8#,Qd5#,Qc4#
1...f1Q 2.Rd5+ Kc4(+pb5) 3.Rd4#
1...h1Q 2.c4+ Kb4(+pb5) 3.c5#

In threat white wants to promote pg7 into queen and mate on 3 different squares. As the threat is without check, Black has enough time to promote both pawns. It would be enough to promote them to bishops to parry threatening mates. White then uses the fact of disappearance of 8th black pawn and mates after Sentinelles selfblock of b5.

a) 1.Rc3 f8Q+ 2.Qxf8(Qd1) Qd4#

b) 1.Qg8 fxg8Q 2.Rf3 Qd5#

c) 1.Rd8 fxe8Q 2.Rxe8(Qd1) Qd6#

Probably the most interesting point of this hybrid problem is the differentiation of solution, reasoning why any solution doesn't work in the other positions. Some other unifying points are mates by wQ on 3 adjacent squares and very active play of Rd3.

1...f8Q 2.gxh1Q(Qd8) cxd8Q(Qd1)+ 3.cxd1Q(Qd8) exd8Q(Qd1)#

More economical version of already published h#2,5 in Anticirce. Roles of wp, wS and wK are executed by wRs pair and this way two promotion moves have richer motivation - they also open indirect batteries.

1.axb8Q 2.Qxd8 3.b8Q 4.Qxb5 5.Kf4 6.Qh4 7.d8Q 8.Qg5 9.g8Q+ e5#

4 wQ promotions have very different motivation: queen born in 1st move goes through d8 to h4 and pins bS, second queen from b8 firmly paralyses bQ, queen promoted at d8 blocks after diagonal move and guards square on the same file, finally last queen promotion provokes battery paralysis resulting in pawn midboard mate.

1.a8Q 2.Qa4 3.Qb3 4.Qxa2(Sg8) 5.fxg8Q 6.Qxg3(g7) 7.hxg7 8.g8Q 9.Qxh7 10.Qxc2 11.c8Q 12.Qc5 13.Qb4 Rb3#

A little bit different seriesmover. Again there are 4 queen promotions, but the critical position before black mating move is a zugzwang, in which Qa2 and Qc2 prevent bishop and rook moves to these squares, Qc2 moreover guards e2, Qg3 guards almost everything around bK and Qb4 leaves the only legal move for Black.