It's a tough choice between Children of the Damned and Moonchild. Moonchild just gets it as it will always hold a special place in my heart. I can still remember taking Seventh Son vinyl out of the sleeve, putting it on the stereo, hearing the soft acoustic guitar, Bruce's vocals, the keyboards.............and then FUCK ME!!! those power chords!! Great heavy riff throughout, two blinding solos, and the best album opener Maiden have done IMO.