I'm not sure if limiting it to metal albums only made this easier or harder.
Anyway, I'm only picking albums that for some reason have clicked for me personally the most and have had a lot of staying power in my listening habits for that reason. As such, I wouldn't really expect many people to agree with me.
10. In Flames - Clayman
9. Arch Enemy - Wages of Sin
8. Behemoth - Evangelion
7. Ensiferum - Iron
6. Helloween - The Dark Ride
5. Kamelot - The Black Halo
4. Iron Maiden - A Matter of Life and Death
3. Amorphis - Silent Waters
2. Iron Maiden - Dance of Death
1. Pain of Salvation - The Perfect Element I
edit: man I don't understand all the love for BTBAM