Top 10 East European Metal Bands

Obviously Poland takes the cake - their bands are heavy and musicians are very proficient.
The Top Ten
1 Behemoth Behemoth is a Polish blackened death metal band from Gdańsk, formed in 1991. They are considered to have played an important role in establishing the Polish extreme metal underground.
2 Vader Vader is a Polish death metal band from Olsztyn. Formed in 1983, the group was founded by then-bassist Piotr "Peter" Wiwczarek and guitarist Zbigniew "Vika" Wróblewski. Starting as a heavy metal group, Vader eventually went to thrash, speed, and then in the late 1980s became a death metal band. The ...read more.
3 Riverside Riverside is a progressive rock/metal band from Warsaw, Poland. It was founded in 2001 by friends Mariusz Duda, Piotr Grudziński, Piotr Kozieradzki and Jacek Melnicki, who shared a love for progressive rock and heavy metal.
4 Infernal War Infernal War is a Polish black metal band formed in Częstochowa in 1997. The band is known for their extreme anti-christian and WWII lyrics, leading them to be mislabeled as a NSBM band. Critics describe the band as "brutal black metal."

One of the heaviest bands I've ever heard - black metal from Poland, formed in 1997. They were originally known as Infernal SS.
I remember in 2016 and 2015 Encyclopaedia Metallum, aka Metal Archives, labeled them as "brutal black metal", which describes them best. Sometime in 2017 Encyclopaedia Metallum changed it to "black metal" - I guess they did it because officially there's no subgenre "brutal black metal".
Infernal War sound like black metal with drumming from technical death metal which creates a more brutal sound.
Their song Spill The Dirty Blood Of Jesus is one of the heaviest songs ever written.

5 Decapitated Decapitated is a Polish technical death metal band formed in Krosno in 1996. The group comprises guitarist, founder and composer Wacław "Vogg" Kiełtyka, vocalist Rafał Piotrowski, bassist Paweł Pasek, and drummer Michał Łysejko.
6 Abominable Putridity Abominable Putridity is a Russian slam death metal band formed originally from Moscow, formed in 2003. The band has released two albums; In the End of Human Existence and The Anomalies of Artificial Origin. They are one of the most popular brutal death metal bands to day. Abominable Putridity shares ...read more.
7 Niburta

A Hungarian metal band formed in 2009 that incorporates tunes, instruments and lyrics from The Balkans although Hungary isn't a Balkan country. Genres - folk metal, death metal, metalcore. I think their folk metal is the most interesting part.
The band have both male and female lead singers. The male provides harsh vocals and growls in English while the female provides angelic clean vocals in a language that is neither Hungarian nor English. She sings in some South Slavic language from a Balkan country - most probably Bulgarian, or Macedonian, or Serbian/ Serbo-Croatian (something like that but I don't know what language is this exactly).
All this sounds very interesting.
Songs I liked: Balkanic Heart, Što Imala Kăsmet, Forebears' Dance, Mašala

8 Pokolgép

One of the first Hungarian metal bands, formed in 1981. Genres - Power/Speed Metal.
They sing in Hungarian. They are still active and in 2016 released a new album (Metalbomb).

9 Master's Hammer
10 Bucovina
The Contenders
11 Umbrtka
12 Dalriada Dalriada is a folk metal band from Sopron, Hungary that was formed in 1998 as Echo of Dalriada, but shortened their name to Dalriada in late 2006. Their third studio album Kikelet and all subsequent albums were successful in the top ten of the official Mahasz music charts.
13 Graveland
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