It's... a thingy? Haha!
Before seeing your art, I had basically had zero exposure to the different versions of Doom other than just the original game. The different monster designs from the later versions/sequels are always interesting to me and sometimes come as quite a surprise, like this one.
One tiny nitpick I have is that I figured that the light from inside the mouths would light up a little bit more of what was right outside of it. Otherwise, really nice work.