In Guitar Hero Metallica, a rhythm game for the Xbox 360, PlayStation 3, and Wii game consoles, the player will be able to unlock special characters for use during gameplay. These characters are popular musicians in the rock genre.

1. Lemmy (5) Rock out as Lemmy
2. King Diamond (5) Rock out as King Diamond

While playing career mode, when the player completes certain songs they will unlock a corresponding character. The characters unlocked are based on songs performed by bands the unlockable musician was a part of.

1. Lemmy: Finish Ace of Spades by Motorhead in career mode
2. King Diamond: Finish Evil by Mercyful Fate in career mode

In addition to Lemmy and King Diamond, several other rockers are unlockable by earning a certain number of stars in the different career modes of the game:

1. James Hetfield: 100 Stars in career (Vocalist)
2. James Hetfield Classic: 150 Stars in career (Vocalist)
3. James Hetfield Zombie: 200 Stars in career (Vocalist)
4. Kirk Hammet: 100 Stars in career (Guitar)
5. Kirk Hammet Classic: 150 Stars in career (Guitar)
6. Kirk Hammet Zombie: 200 Stars in career (Guitar)
7. Lars Ulrich: 100 Stars in career (Drums)
8. Lars Ulrich Classic: 150 Stars in career (Drums)
9. Lars Ulrich Zombie: 200 Stars in career (Drums)
10. Robert Trujillo: 100 Stars in career (Bass)
11. Robert Trujillo Classic: 150 Stars in career (Bass)
12. Robert Trujillo Zombie: 200 Stars in career (Bass)