Saraf is an experimental solo project of Serafima Okuneva, the bassist of St. Petersburg doom metal band Prophecy of Sheva. Surprisingly, I haven't heard about her until very recently (thanks to this interview), even if she's called the "first lady of ritual black noise" and the idea behind Saraf is relevant to my interest. Although Serafima grew up in Komi, her father is Northwestern Mari, and most of her solo works are based on Mari culture or folklore in one way or another.
This particular album is dedicated to the summer solstice, as well as to "Mari people,their deep culture and their strong faith" (release notes). It consists of one long track that mixes up experimental noise, folk and some elements of black metal, and I'd say it's more accessible than her debut album "Azyren" that was released two years before and has the same themes. She has also made several collaborations with various metal and experimental musicians, and started another solo project called Ovda mostly focused on dungeon synth. Anyway it's nice to find out about another industrial, experimental, or metal project with Finno-Ugric themes, as there isn't much music in minority FU languages apart from pop and traditional folk, and hopefully I'd be able to travel to Mari El and hear some Mari music live this summer.