This is my top albums (only with those where I gave 8 or more). I will update the list now and then.
Keep in mind that I've only been seriously listening to metal for a few years, and that it's not because an album is recent that it deserves to be on the list any less than a classic of the genre, that doesn't matter to me, an album makes the list when I like it, that's the only criterion that counts.

Bands that appeared more than once:
9: Opeth

6: Finsterforst, Moonsorrow

5: Dream Theater, Galneryus, Megadeth

4: Agalloch, Black Sabbath, Bolt Thrower, Children Of Bodom, Draconian, Iron Maiden, Leprous, Metallica, Septicflesh, Shadow Of Intent

3: An Abstract Illusion, Be'lakor, Blind Guardian, Born Of Osiris, Carcass, Coroner, Cradle Of Filth, Death, Haken, Immortal, Judas Priest, Mgła, My Dying Bride, Nightwish, Pantera, Paysage D'Hiver, Porcupine Tree, Rhapsody, Slipknot, Symphony X, W.A.S.P.

2: After The Burial, Alcest, Archspire, Blaze (JPN), Candlemass, Cattle Decapitation, Dimmu Borgir, Dissection, Dvne, Elder, Emperor, Ensiferum, Funeral, Gorod, Gris, Helloween, Isis, Kalmah, Kamelot, Malediction, Motörhead, Neurosis, Nevermore, Paradise Lost, Psychonaut 4, Rush, Sepultura, Shylmagoghnar, Sigh, Swallow The Sun, Tool, Trhä, Windir, Wintersun, Witherscape

Number of albums per country:
1. USA 🇺🇸: 110
2. United Kingdom 🇬🇧: 48
3. Sweden 🇸🇪: 41
4. Finland 🇫🇮: 29
5. Germany 🇩🇪: 25
6. Norway 🇳🇴: 22
7. France 🇫🇷: 14
8. Switzerland 🇨🇭: 10
9. Canada 🇨🇦: 9
9. Japan 🇯🇵: 9
10. Australia 🇦🇺: 8
10. Greece 🇬🇷: 8
11. Poland 🇵🇱: 5
11. The Netherlands 🇳🇱: 5
12. Italy 🇮🇹: 4
13. Brazil 🇧🇷: 3
13. Denmark 🇩🇰: 3
13. Iceland 🇮🇸: 3
14. Belgium 🇧🇪: 2
14. Chile 🇨🇱: 2
14. Georgia 🇬🇪: 2
14. Portugal 🇵🇹: 2
14. Russia 🇷🇺: 2
14. Spain 🇪🇸: 2
15. Andorra 🇦🇩: 1
15. Argentina 🇦🇷: 1
15. Austria 🇦🇹: 1
15. Belarus 🇧🇾: 1
15. China 🇨🇳:1
15. Israel 🇮🇱: 1
15. Romania 🇷🇴: 1