Editing Babson task (section)

==The cyclic Babson==
{{Chess diagram
| tright
| '''Peter Hoffmann''', ''Die Schwalbe'', 2003

|rl|  |  |  |bl|  |rd|  
|  |  |  |  |  |  |  |pl
|bl|  |  |  |bd|kd|nl|pd
|pd|  |  |  |  |  |pd|rl
|kl|  |  |nl|  |pd|pl|  
|  |  |pl|  |  |pl|  |  
|pl|bl|pd|pd|pd|  |  |ql
|  |  |bl|  |nl|  |  |  

| White to play and mate in four
}}
In a cyclic Babson, rather than Black’s promotions being matched by White, they are related in cyclic form: for example, Black promoting to a queen means White must promote to a bishop, Black promoting to a bishop means White must promote to a rook, Black promoting to a rook means White must promote to a knight, and Black promoting to a knight means White must promote to a queen.

The August 2003 issue of the German problem magazine ''[[Die Schwalbe]]'' contained the problem to the right, a mate in four by [[Peter Hoffmann (chess composer)|Peter Hoffmann]]. Hoffmann had previously published a number of conventional directmate Babsons, but this one is significant because it is the first cyclic Babson. However, as with Drumare's original Babson task, the problem uses promoted pieces and has a capturing key.

The key is 1.Nxe6, threatening 2.hxg8=Q and 3.Qf7#. The thematic defences are:

*1...d1=Q 2.hxg8=B (2.hxg8=Q? Qd7+ 3.Bxd7 stalemate; 2.hxg8=N+? Kxe6 and no mate), threatening 3.c4+ Q-moves 4.BxQ#
**2...Qd7+ 3.Bxd7 Kxg6 4.Rxh6#
**2...Qxc1 3.Rxg5 (threat: 4.Rf5#) hxg5 4.Qh8#
*1...d1=B 2.hxg8=R (2.hxg8=Q? stalemate; 2.hxg8=N+? Kxe6 and no mate) Kxe6 3.Rd8 3.Kf6 Rd6#
*1...d1=R 2.hxg8=N (2.hxg8=Q? Rd4+ 3.c4 stalemate) Kxe6 3.Qxe2+ K-moves 4.Qe5#
*1...d1=N 2.hxg8=Q (2.hxg8=N+? Kxe6 3.Qxe2+ Ne3! and no mate) Nxb2+ 3.Kb5(Bxb2) and 4.Qf7#

There are also a number of sidelines.

{{Chess diagram
| tright
| '''Peter Hoffmann''', ''Schach'', 2005

|  |  |  |  |  |rd|  |nl  
|  |pl|pl|  |pl|  |  |  
|  |pd|pl|  |kd|pl|  |  
|pd|  |  |nl|  |pd|  |pl
|kl|  |  |  |  |pl|  |  
|  |  |bl|  |pl|  |  |  
|  |rl|pd|pd|pd|  |  |  
|  |  |ql|  |rl|  |  |  

| White to play and mate in four
}}
In the September 2005 issue of ''{{ill|Schach (magazine)|lt=Schach|de|Schach (Zeitschrift)}}'', the first cyclic Babson without promoted pieces in the initial position was published. Again, the composer was Peter Hoffmann.

The key is 1.Nxb6. The thematic defences are:

*1...d1=Q 2.exf8=B (2.exf8=Q? Qd4+ 3.Bxd4 stalemate; 2.exf8=N+? Kd6 3.Be5+ Kc5 and no mate)
**2...Qd4+ 3.exd4 Kxf6 4.d5#
*1...d1=B 2.exf8=R (2.exf8=Q? stalemate; 2.exf8=N+? Kd6 3.Be5+ Kc5 and no mate)
**2...Kd6 3.Qd2+ with mate after any move by black
*1...d1=R 2.exf8=N+ (2.exf8=Q? Rd4+ 3.Bxd4 stalemate; 2.exf8=B? Rd7 3.c8=Q(B) stalemate)
**2...Kd6 3.Be5+ Kc5 4.Qxc2#
*1...d1=N 2.exf8=Q (2.exf8=N+? Kd6 3.Be5+ Kc5 and no mate)
**2...Nxc3+ 3.Kxa5 Ne4 4.c8=Q#
{{-}}