[Retros] Another royal 5.5# (and three 5.0#'s)

[Noam Elkies]

> # K: (discovered #)

> Ke1/Qd1     SPG in 5.5 - NDE 10/02

> Ke1/Bc1     SPG in 5.5 - CF 10/02


Ke1/Bf1     SPG in 5.5 - NDE 10/02
1 e4 e5 2 Qg4 Ke7 3 Ke2 Kd6 4 Q:d7+ Kc5 5 Qd6+ Kc4 6 Kd1# (C+, 100 msec.)

Black can do it in just 5.0:
1 e4 e5 2 Ke2 Qf6 3 Kd3 Ke7 4 Kc4 Qa6+ 5 Kc5 Ke6# (C+, 10 msec.)
1 e3 d5 2 Ke2 Qd6 3 Kf3 Kd7 4 Kg4 Qg3+ 5 Kf5 Kd8# (C+, 20 msec.)
1 e4 e5 2 Ke2 Bb4 3 Kf3 Ke7 4 Kg4 h5+ 5 Kg5 Ke6# (C+, 10 msec.)

NDE