Shelley has seen Behemoth 6 times.

Behemoth is often considered one of the pioneers of the Polish extreme metal movement of the 1990s. While the band's first three albums were black metal, "Satanica" (1999) and "Thelema.6" (2000) incorporated death metal to create a unique blackened death metal sound. Throughout the 2000s, Behemoth expanded its influence globally, touring in Scandinavia, the United Kingdom, and North America for the first time in 2003. Over the next two decades, the band toured extensively with some of metal's most popular and influential bands including Slayer during the band's farewell tour in 2018. In 2022, Behemoth released its twelfth studio album "Opvs Contra Navtram" in honor of its thirtieth anniversary.