Pinned piece unpinned and pinned again 2

1.Ba2! th. 2.Kxa5 e1Q,e1B#
1...Sc5 2.Qxe2 Scb3#
1...c5 2.Qxb2 c4#
1...Rfxe5+ 2.Bd5 Rxd5,e1Q,e1B#
1...Rexe5+ 2.Bd5 e1Q,e1B,Rxd5#
1...Rxf4 2.Rxa5 Rb4#
1...e1Q+ 2.Bc4 Bxc4,Qb4,bxa6#
1...b6, Rxa6 2.Sc8 c6#
1...Sc6 2.Qc5 Rxc5#
1...Sc4 2.Ra5 Sa3#
(1...Qe1,Sb3 2.~)

A wealth of variations with the pair of thematical unpins and repins of the wQ. Both indirect unpins (by pawn and knight) are done on the same square c5 and wQ has to choose carefully the repin square - b2 or e2. White has to take into account that the battery mate should cut the line of wBa2 as well as avoid cutting the pin line.

1.Rg6! th. 2.Rf6 Rxe5#
1...Sd5 2.Sxd7 Sf6# (2.Sxf7?)
1...Sc5 2.Sxf7 Se6# (2.Sxd7?)
1...Rxe5+ 2.Kf6 Qd8#
1...f1Q,R+ 2.Kxe4 Qf4#
1...d6+ 2.Kf6 Bxe5#
1...fxg6+ 2.Kxe4 Rxe5#
(1...Bxe5 2.Rg5 d5#
1...d5+ 2.Kf6,Re6
1...Sd~ 2.Sxe4 f1Q#
1...Sf4 2.~ fxg6#
1...f6 2.~ Rxe5#)

Two main variations with unpins by two knights lead to two battery pin mates, again with the choice of the right repin line. The motivation behind the precise choice is not totally obvious: black has to guard e4 and f4 respectively, but should not cut the bishop lines to f6 and e4 respecively.

1.Sdxf4! th. 2.Kxf6 Sed7,Sxg4#
1...Se~+ 2.Bc5+ Rxc5#
1...Sed7+! 2.Sc5 Sb8#
1...Sf3+! 2.Sd5 Sd4,Se1#
1...Sd3+! 2.Qd5 Sxc1#
1...Sxg4+! 2.Bc5+ Se3#
1...Sh7,Sfd7 2.Qd3 Qxd3#
1...Sfg6,Sxe6 2.Rxc3 Rxf4#
And now something even more complicated. Key knight pins itself and White has three pinned pieces, unable to parry the mate following the random check by bS. Therefore Black makes three corrections involving unpinning the white trio. White pieces repin on the 5th rank and Black batteries give varying mates. Great B-W interplay.

1.Qh5! th. 2.Sbxc3 Rxc3#
1...Qxa4 2.Rxc3 Qb5#
1...Rxc8 2.Bxc3 Rd8#
1...Bxh5 2.Sexc3 Bg6#
1...Kd7 2.Bxc3 Kxc8#
1...Qd7 2.Rc6 Qxd4#
1...Sd5 2.Bxe3 Sf4#
1...Qc6 2.Bxb3 Qxe4#
1...Sf5 2.R8xc7 Rxd4#
1...Bf7 2.Qf5 Bxc4#
1...Rxb1 2.Bd1 Rxd1#

Well, one can argue whether this is or isn't even better example of interplay with its 11 different mates. More importantly, in the first three variations Black unpins and selfunpins, White selfpins always on c3 and Black mate sby switchback. Further there are 3 variations with unpin of white piece by Black and 3 variations with unpin of mating black piece by White. The final variation is just by-variation, yet it still works perfectly. The only blemish I see in the repetition of 2.Bxc3.

1...Rxf5 2.Sxf6 Rxd4#
1...Qe1 2.Sxf2 Rxd4#

1.d5! th. 2.Rh1+ gxh1Q#
1...Sf4 2.Sxf6 Se6#
1...Bb4 2.Sxf2 Be1#
1...Rxg4+ 2.Kxg4 Ra4#
1...Sh2 2.d6 Rxg4#

In the set play wS selfpins on f2 and f6, but that is not thematical for 25th TT CCM as wS was not pinned before.

Then the key introduces the pin of wS, i.e. it is an example of a problem, where the first thematical pin is not present in the diagram position.

There are two thematical variations unpinning the wS and the knight pins again on the same pair of squares as in the set play (leading to the play transference), now for the battery mate. There is nothing particular in 2.Sxf6 variation, however 2.Sxf2 stands out thanks to the dynamic nature of battery mate pinning the wS only in the latest possible moment.

By-variations are precise as well, e.g. 2.d6 is the only tempo move available to White after 1...Sh2.