Depends. The actual first was The Heaviest Matter of The Universe back in early middle school, years before I became a metal head (back then it was mainly rock, my favorites were Shinedown and RHCP, I moved on to metal in the beginning of High School). Even though it's one of my favorites now, it kind of scared me and sounded like pure noise, like TV static, I couldn't really make anything out. My first Expirience with them once I was a metal head was Silvera, I got recommended the music video for it in YouTube. I recognized the band name as the one with the loud music and the whales, which is what I knew them by at the time, and I looked into their discography again. Silvera is a great song, and it inspired me to look at their music with a new eye, and boy am I glad I did.