Metallica is one of my favorite older bands! 
Same here. The black album played a big part in my formative years
What was their most popular song do you know?
I think Enter Sandman. They we great early heavy metal
I love Enter Sandman! The Unforgiven is another favorite of mine.
Enter Sandman
"Enter Sandman" is a song by American heavy metal band Metallica. It was released as the first single from their self-titled fifth album, "Metallica" in 1991. The music was written by Kirk Hammett, James Hetfield and Lars Ulrich. Vocalist and rhythm guitarist Hetfield wrote the lyrics, which deal with the concept of a child's nightmares.
The single achieved platinum certification for more than 1,000,000 copies shipped in the United States, spurring sales of over 30 million copies for "Metallica
child, and has said they were the reason he wanted to play guitar.
He was also a fan of 70s & 80s hard rock and heavy metal bands, including White Lion, AC/DC, Iron Maiden, Queen, Black Sabbath, Deep Purple and Bon Jovi.
Masterpiece occasionally played cover songs by these bands, including Queen's "I want to break free", Bon Jovi's "It's my life," and Metallica' "Enter Sandman".
He has also cited Led Zeppelin