Selections 8

1...CHc8(S)+ 2.Ka6 CHa7(B) 3.CHb6(Q) CHxb6(wR) 4.CHb7(Q)#
          3...CHb8(R) 4.CHc7(S)#

1.Ka6! zz
1...CHc8(S) 2.CHa7(Q)+ CHxa7(wB) 3.CHd4(R) ~ 4.CHd8(Q)#
1...CHxb7(wS) 2.CHa5(B) th. 3.CHd8(R)#
     2...Kb8 3.CHc3(R) Ka8 4.CHc8(Q)#

Fairy condition Andernach chess implies Black capture by chameleon actually leaves him without defence force.

It is quite surprising that the present position is mutate, but everything is ready, other set plays end in shorter mates. After the key the play is changes and generally White takes advantage of the very limited position of the bK.

1.BLd1<->BLd5! f5 2.BLd5<->BLd1 f4 3.BLd1<->BLd5 f3 4.BLd5<->BLd1#

Simple demonstration problem for the Messigny chess. White uses advantage of the first move to gain upper hand in the tempo play and does not let Black escape, only black pawn can move.

1.e7! th. 2.e8L#
1...Kd3 2.d7! (th. 3.d8L#) Kc4 3.c7! (th. 4.c8L#) K~b/K~d 4.b8L/d8L#
1...Kf3,Kf2 2.f7! (th. 3.f8L#) Lxc6-c7 3.f8L+ Lxe7-f7 4.Lxf7-f6#
     2...Kg4,Kg3 3.g7! (th. 4.g8L#) K~f/K~h 4.f8L/h8L#
1...Lxc6-c7 2.e8L+ Lxd6-e5 3.Lxe5-e4+ Kxe4-e5 4.f7 or b8L#

The fairy condition is in this case questionable - some people treat transmuting kings as fairy pieces (including myself), and even Popeye allows it as both fairy condition and fairy piece. But in this case let's understand it as fairy condition. Locust is on the other hand quite clearly piece with very specific properties. Checking transmuting king by locust offers Black very limited movement possibilities, therefore white tries to take advantage of this by checking black transmuting this way. As there is not much black meat for white locust moves, it is necessary to create new locusts by promotions.

a) 1.d5? th. 2.Be2#, 1...g1S!

1.Bd2! (th. 2.Rc3+ Kxd4 3.Sc2#) g1=N 2.d5 (th. 3.Be2+ Nxe2(Bf1) 4.Bxe2(Ne1)#)

b) 1.Bd2? th. 2.Rc3+ Kxd4 3.Sc2#, 1...g1N!

1.d5! (th. 2.Be2#) g1S 2.Bd2 (th. 3.Rc3+ Kd4 4.Sc2#)

Quite paradoxical choice of promotions by Black - S/N. Although knight movement is just a part of the nightrider movement, thanks to Circe there is a world of difference - bS is reborn at b8 or g8, bN normally on the first rank. One pawn less in the twin then means complete exchange of try and solution between two positions.

1.Gf3! th. 2.Rh5#, Bg3#
1...Gbe5 2.Rxe5(Ra1) (th. 3.Bg3#)
     2...Bxf3(Bc8) 3.f3! (th. 4.Bg3#)
     2...Gg1 3.Bg3+ Gc1 4.Rxc1(Ra1)#
1...Gae5 2.Bxe5(Bc1) (th. 3.Rh5#)
     2...Rxf3(Ra8) 3.f3! (th. 4.Rh5#)

The key introduces two threats by means of ordinary Novotny on f3. Black parries both of them by his own Novotny on e5. And then comes the decision moment for White: which piece has to capture on e5 to free the way for the other piece? It turns out that the action is needed from the piece that could be jumped over by the remaining bG. This creates single threat that can be parried in an analogous fashion by black annihilation on f3. Repeated line closing 3.f3 is a decisive step to the checkmate in the next move.

1.Sa5! th. 2.Sb7+ Gfxb7(Gb1) 3.Sf7+ Gxf7(Gf1) 4.Rd5#
     2...Gdxb7(Gb1) 3.Rd5+ Gxd5(Gd1) 4.Sf7#
1...Gfb7 2.Sf7+ Gxf7(Gf1) 3.Rd5+ Gxd5(Gd1) 4.Sb7#
1...Gdb7 2.Rd5+ Gbxd5(Gd1) 3.Sb7+ Gxb7(Gb1) 4.Sf7#

The play in the threat and two variations is motivated quite easily: White always has to check bK on empty square. Captures are of no use as then White piece would have to be reborn. On the other hand, Black capturing piece leaves for the 1st rank as well. There is no specification of the order of moves in the threat, so that there is no pure cycle in the problem. From this point of view, the next problem is more successful attempt.

1.Sc7! th. 2.GNe3+ Sxe3(Sb8) 3.GNc4+ GNxc4(GNc1) 4.GNf5#
1...GNe3 2.GNf5+ GNxf5(GNf1) 3.GNe3+ Sxe3(Sb8) 4.GNc4#
1...Se3 2.GNc4+ GNxc4(GNc1) 3.GNf5+ Sxf5(Sg8) 4.GNe3#

Here the basic mechanism is the same, but there are important details making the cycle of move pure: - GNf5 cannot capture on e3 due to blocked e1, - after 1...Se3, the knight cannot capture on c4 and also not on f5, the latter constraint is removed in the variation when GNg8 captues on f5 in the B3 move.