Nergal

In this photo, which was posted on Behemoth's Instagram page, Nergal can be seen in front of the Peavey 6505 amp head.

According to guitar.com, Nergal used the amp during for his side-project, Me And That Man, and the 2021 album "New Man, New Songs, Same Shit, Vol. 2".

Nergal’s not using the same guitar gear for Me And That Man as he is for Behemoth. It’s “a completely different set of tools,” he tells us, starting with his amplifier. “It’s some Peavey Classic combo I got years ago. I remember, I was hooked up with Peavey through Behemoth – I was using their 6505, and I asked them about an amp for Me And That Man and they sent this vintage-sounding combo. So it’s that combined with a Gretsch, it doesn’t really need much more than just a boost in between. For the recent shows I used my LCFR boost pedal, which is obviously meant for extreme metal, but I tried it for the blues-oriented stuff and it did the trick as well.”

Nergal has consistently used the Laboga Mr. Hector guitar amplifier head throughout his career, as evidenced by a user-uploaded photo on Vk.

Behemoth - The Making of Evangelion (Documentary) -13:24 Mesa Boogie Roadking

in 3. 17 you hear that it was used to "introduce extra harmonics". An album released in 2018 was recorded on it

In the YouTube video "Behemoth ILYAYD Recording & Production Studio Sessions," Nergal is seen using the Bogner Uberschall 120-Watt Tube Guitar Amp Head at the 3:11 mark. This amplifier was used to record Behemoth's 2018 album and is also a staple in Nergal's live performances and recent recordings.

Nergal consistently uses the Mesa/Boogie 4x12 Cabinet, as shown in a user-uploaded photo on Vk.