Selfmates 8

1.Bc8! zz
1...Rd7~ 2.d6+ Rxc5#
1...Rd6! 2.Qc3+! Rxc3#
1...Rxd5! 2.Bd7! Rxc5#

Any move of Rd7 opens Bc8 to d6, allowing pd5 to leave. Correction Rd6 stops the pawn, but unpins Rc7, other correction Rxd5 captures pawn, but puts Black into other zugzwang.

1.Bg8! zz
1...Se6~ 2.Rxc2+ Bxc2#
1...Sd4! 2.Qd2+! Qxd2#
1...Rb6~ 2.Qd2+ Qxd2#
1...Rxb3! 2.Rxc2+! Bxc2#

All is about covering or blocking bK flights. Any move of Se6 opens Bg8 to b3, allowing Rb2 to leave. Correction Sd4 guards c2, but blocks d4. On the other hand, any move of Rb6 opens Ba7 to d4, while correction Rxb3 cures this by providing flight c4, but it also block b3. Good example of reciprocal corrections.

1.Sc4! th. 2.Sd2+ Sxd2#
1...Rc5~ 2.Qe3+ Sxe3#
1...Rxc4! 2.Sdb6! Sf1~#
1...Rxd5! 2.Scb6! Sf1~#

Key creates white halfbattery that is subsequently transformed into masked pin and normal pin during correction variations. Black parries threat by any move by Rc5 that opend Qa6 to e3. Two corrections neutralize that by direct guarding of e3-b3 line, but as black rook enters halfbattery line, white pins it by moves reclosing a7-g1 line.

1.d4! zz
1...Sc5~ 2.Bf4+ Re2#
1...Se4! 2.Bd2+ Rxd2#
1...Sh5~ 2.Rg2+ Rf2#
1...Sg3! 2.Re2+ Rxe2#

Pair of analogical corrections. Any move of Sc5 (Sh5) removes guard from e5-e1 (h4-e1) line, allowing the only avaliable battery check that isn't the mate to Black and allows mate from Ba3-Rb2-Kc1 battery. Correction works as follows: Sc5 (Sh5) enters line in question making the secondary threat not-checking move, but as there is no longer any danger of doublecheck mate in Bd2+ (Re2+) move, it becomes White's answer to Black correction, also using the pin of Se4 (Sg3). Good analogy.

1.Bc1! th. 2.Rh2+ Bd2#
1...Sd6~ 2.Rc6+ Bc3#
1...Sb5! 2.Rd2+! (Rc3+? Sxc3!) Bxd2#
1...Sc4! 2.Rc3+! (Rd2+? Sxd2!) Bxc3#
1...Sb7!, Se4! 2.Sb4+! Bxb4#

Any move of Sd6 defends threat by opening b8-h2 line, but it allows secondary threat by opening h6-c6 line. Corrections Sb5 and Sc4 defend that too, but close f1-a6, seemingly allowing two continuations Rd2+ and Rc3+. But here comes into effect dual avoidance motives of moves Sb5 and Sc4 - they guard c3 and d2 respectively. Excellent pair of black corrections!

Other two correction close the line f3-a8, but there is no dual avoidance here and they allow the same continuation. Anyway, this in fact one other correction adds to the content and shows that V. Rudenko is able to drill maximum from given scheme.

1.Sd2! zz,
1...Sc8~ 2.Qc4+ Bxc4#
1...Sd6! 2.Sb3+! Bxb3#
1...Bg8~ 2.Qd6+ Sxd6#
1...Bd5! 2.Bxb6+! Sxb6#

After random black moves by two thematical pieces White must take care about his queen guarding h8-b8 line, corrections parry queen checks by direct guarding and interposing, any way they carry error of closing queen line to 8th rank and thus allow other white attacks leading to battery mates.

1...Sd6, Sf6 2.Qf4+, Bf4+ Qxf4#, Qxf4#

1.Sd6? th. 2.Sxe4+ Qxf4#,
1...Se4~, Sf6! 2. Qf4+, f4+ Qxf4#, Qxf4#
1...Rxf2!

1.Sf6! th. 2.Sxe4+ Qxf4#,
1...Se4~, Sd6 2. Bf4+, f4+ Qxf4#, Qxf4#
1...Rxf2 2.Sf3+ Rxf3#

This problem is quite different from all previous as it shows changed play after correction moves with regard to set play and corrections appear in 2 phases. Also, attack f4+ is transfered. Yes, we are in 90's...