Heavy Metal and lyrics has Gayatri mantra "Oṃ bhūr bhuvaḥ svaḥtát savitúr váreṇ(i)yaṃ"
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There is an entire sub-genre of Sanskrit inspired metal called "Vedic Metal". Only a few bands are active in that category. Maybe its one of their songs. Check out Rudra, a famous vedic metal band from south-east Asia. Also, a lot of bands in India have used various 'mantras' as lyrics of their songs. Check out "The Down Troddence" from Kerala, India. But then again, its not heavy metal, its more of a trash-inspired composing style.