Colin Sydenham
Superpins is a fairy condition in which pinned pieces cannot check or
pin. Colin Sydenham has probably done more than any other composer to
popularise the condition. The interest in this simple example resides in
why alternative moves of the key piece fail.
Any move of the white king will threaten 2.Sg6 mate, and the variation 1...e3 2.Qd4 features in all phases.
1.Kf7? fails to 1...Rf1!, when after 2.Sg6 the king can escape to e3 or g3, because the f5 knight is pinned.
1.Kg7? fails to 1...Rg1! and after 2.Sg6 Rxg4! pins the knight. 1.Kh7? fails to 1...Rh1! 2.Sg6 Kg5!
1.Kh6? is refuted by 1...Rd1! 2.Sg6 Rd6! pinning the knight. Finally 1.Kh5? fails to 1...Rb5! 2.Sg6
and again the king can escape to e3 or g3. The key is 1.Kf6! threat 2.Sg6. The king guard on e5 frees the
queen for 1...Rf1 2.Qxf1. The condition is exploited each time, and arranging different refutations for five
tries from such a light setting is quite an achievement.