Solver's impressions 7

I saw Black has no move in initial position, but I wasn't able to find any #3 key and continuation. Thus I set the position into Popeye and I was left amazed by very interesting content.

1.Nc5! zz,
1...Qa2 2.g5! f6~ 3.h8B# (3.h8Q?)
1...Qc2 2.Rf1! f5 3.h8B# (3.h8Q?)
1...Qc4+ 2.Ke6! f5 3.h8B# (3.h8Q?)
1...Qb7+ 2.Nd7! f5 3.h8B# (3.h8Q?)
1...Qb4 2.Bd8! f5 3.h8B# (3.h8Q?)

1. Key gives bQ 5 possible moves, of them 2 checks!
2. Although the mate is the same in all variations, motivation leading to it isn't trivial - White makes pf6 move by various pieces (Ba5, Rc1, Kd5, Nc5, pg4).
3. Unfortunately (found by Popeye too), nightrider is needed only in 1...Qb7+ variation for covering b3.
4. Many Beamtenschach construction tricks used - well done!

a) 1.b5 2.Bxc4 ... 5.b1B ... 8.Bb8 Ba6#
b) 1.c5 ... 3.cxd3 ...5.d1R ... 8.Rb8 Rc3#

Nice analogy for such economical position - line clearance in form of reciprocal Zilahi isn't seen often.

1.f3 f5 2.Kf2 Kf7 3.Kg3 Qe8 4.Kh4 g5+ 5.Kh5 Kf6#

Peter Rössler did already better in this genre...

1.g1B ... 3.Be5 Bb3#
1.gxh1Q ... 3.Qe5 Bb3#
1.gxf1R ... 3.Re5 Bb3#
1.d1S ... 3.Be5 Bb3#

Trivial AUW, uneconomical...

a) 1.Kd3 2.Kxd2 3.Kc3 4.Gb3 5.Kb2 6.Gb1 7.Ka1 Sc2#
b) 1.Kf5 2.Kg6 3.Gg7 ... 6.Kh8 7.Bg8 Gh6#

Opposite corner mates - at least models, but no deep strategy.

1.cxb3 2.b2 3.b1N 4.Nd5 Kf2=
1.cxd3 2.d2 3.d1N 4.Nf2 Nb4=

Two nightrider promotion - content not worth so much material.

1.d1B 2.Bc2 3.Bh7 4.Qa5 5.c5 Qxh7#
1.g1B 2.Be3 3.Bh6 4.Qd5 5.Qg2 Qxh6#

Well constructed.

1.Rf7 2.Re3 3.Qc1 4.Rc3 5.Re7 6.Rc5 Rxc1#
1.Re7 2.Rc5 3.Ba3 4.Rc3 5.Rf7 6.Re3 Rxa3#

Nice geometrical play, interplay of 3 rooks and D-O echoed model pin mates. Good result!

1.Kh8! f6 2.g8S! f5+ 3.Kh7 f4+ 4.Kh6 f3 5.Sxh2 Rxh2 6.Se7! Rh1 7.Sc6 Rh2 8.Sa5 Rh1 9.Sb3#

Very good constructional point lies in making knight's path to b3 unique - White mustn't cut bBs lines. Accurate timing. Despite no black counterplay interesting problem.