Award of 25th TT Spisska Borovicka C 26.9.2013

1.g8Q! th. 2.e6#
1...Se6 2.Re4#
1...Be6 2.Qf2#
1...Re6 2.Sb5#
1...Qe6 2.Sc2#
1...e6 2.Qxc5#

5 thematic variations with 5 different pieces as defences.

Fairy pieces:
   grasshopper f3, h6 - d4
   lion c2
   zebra c8
   camel g3
   alfil h4
   giraffe + pawn a2, a4
   camel + pawn b2, b4
   dabbaba + pawn c3
   4:5 leaper + dabbaba f8
   0:3 leaper + pawn c6
   0:5 leaper + 3:3 leaper f1
   1:5 leaper + 2:6 leaper g1
   2:4 leaper d2

1...Kc6 2.LOxe6-f7+ Sf6#

1.Sb5! th. 2.c6+ Se5#
1...LOxb5-c6 2.LOxe7-d8+ Ke5#
1...Bc6 2.LOxc3-d3+ Kc4#
1...Kc6 2.LOxe6-f5+ Sf6#

Selfmate with three varations, plus changed set play.

1.Se2 ! th. 2.e4#
1...Be4 2.Nxd6#
1...Re4 2.Rxg5#
(necessary additional motif: unguard g5. 2.axb8QN?/Nxd6? Re7!/Kg4! triple avoidance)
1...Ne4 2.axb8QN#
1...QNe4 2.Sd4#
(necessary additional motif: unguard d4. 2.axb8QN? QNxb8! dual avoidance)
1...Bxe3 2.Nxe3#

Four thematic defences, some of them with interesting dual- and triple-avoidance.

1.c3? th. 2.Ge5# A
1...e5! a

1.c4? th. 2.b4# B
1...Gb4! b

1.NHf8! th. 2.Bb6#
1...e5 a 2.b4# B
1...Gb4 b 2.Ge5# A
1...Gd6 2.Gc5#
1...BHc4+ 2.Sxc4#

Hannelius theme.

1.Qb7! th. 2.Sc6#
1...Rec6 2.Se6#
1...Sc6 2.Be7#
1...Qc6 2.Qd7#
1...Rcc6 2.Qc8#
(1...Ba7 2.Qc7#)

Four unified anticirce variations in an attractive position.

Author's comment: 4 thematic variations, showing the 2 forms of Umnov theme (the black move being Umnov 1 and Umnov 2, and the mate being Umnov 1, so in fact we get 4 chains of Umnov 1 theme), in a quite light setting.

1.LEf4? th. 2.LEf3#
1...LExf1 x 2.LExf1#
1...LEf3!

1.Ra6? th. 2.LEd3# A
1...LEf3 a 2.LExf3# B
1...LEd3 b 2.Qxa1# C
1...LExf1 x 2.Qxa1#
1...LEe4!

1.Bb3! th. 2.LEf3# B
1...LEf3 a 2.Qxa1# C
1...LEd3 b 2.LExd3# A
1...LExf1 x 2.LExf1#

Shedey cycle with 1+1 thematic defences.
Furthermore, a third phase with thematic refutation.
And a non-thematic three-phase changed mate.

1.Rxb4(Ra1)? A th. 2.Qb4# B
1...Rb4 a 2.axb4(Pb2)# C
1...EAb3!

1.axb4(Pb2)! C th. 2.Rb4# A
1...Rb4 a 2.Qxb4(Qd1)# B
(1...EAc4 2.b3#)

Djurasevic cycle with all W and B thematic moves on the same square.
Pity, that the EAgles and paralyzing pieces were needed.

1.LExb2? th. 2.Rb4# A
1...PAb4 a 2.Rc3# B
1...Sd5 b 2.Rxc5# C
1...PAc3 c 2.Rxd4# D
1...PAa3!

1.LEa3! th. 2.Rc3# B
1...PAb4 a 2.Rxc5# C
1...Sd5 b 2.Rxd4# D
1...PAc3 c 2.Rb4# A
1...VAd4~ 2.LExa6#

Completely original 4-fold Shedey cycle.
However, only 1+1 defences are thematic.

1.Bxg3(Pd3)? th. 2.GNb3# A
1...Bxg3(Bb3) 2.GNd7# B
1...d2!

1.Bxg3(Pd5)? th. 2.GNd7# B
1...Bxg3(Bd7) 2.GNh5# C
1...d4 2.GNf2#
1...Rd8!

1.Bxg3(Pf5)? th. 2.GNh5# C
1...Bxg3(Bh5) 2.GNf1# D
1...f4!

1.Bxg3(Pf3)! th. 2.GNf1# D
1...Bxg3(Bf1) 2.GNb3# A
1...f2 2.GNxf2(d4)#

A good contribution to the question what is the same move and what is not.
In my opinion, the problem cannot be seen as 4-fold Ukraininan cycle.
Once we consider the 4 keys on c7-g3 different (and they are!), then we must do the same with the defence(s) b8-g3.
Anyhow, simple and beautiful.

1.Sc7! th. 2.Se8#
   not 2.Sd5+? Kxf5!(Ke8)
   not 2.Bxd1(Bf1)+ Kxf7!(Ke8)
   not 2.Kg5?? self-check (e8 is free)
1... Re8 2.Sd5#
   not 2.Bxd1(Bf1)+ Qxf7(Qd8) : d8 is UNBLOCKED!
   not 2.Kg5+ Re1+! : e1 is BLOCKED!
1... Se8 2.Bxd1(Bf1)#
   not 2.Kg5?? Self-check by Ph6 : g7 is UNBLOCKED!
   not 2.Sd5+ Qg1! : g1 is BLOCKED!
1... Be8 2.Kg5#
   not 2.Sd5+ cxd5(d7) : d7 is UNBLOCKED!
   not 2.Bxd1(Bf1)+ Rd1! : d1 is BLOCKED!
1... Kxf5(Ke8) 2 Rxb1(Rh1)#

By far the best problem in the tournament.
Just in single phase, it shows highly original cyclic trial-avoidance idea:
In each of 3 main variations, one of the mates in disabled because of unblocking Black rebirth square, and the other one because of unblocking White rebirth square.
Plus an extra thematic K defence (with rebirth on the threat square) is added.
May not so difficult to build, but highy original and impressive.