From DOOM Eternal: The Ancient Gods Part 2 DLC. Sometime after the demonic envision, nature is reclaiming the land. The "gore" from the original invasion eventually died off and became almost stone like/decaying plant like in nature which is what the larger grey vine structure is. I've also included an original pass created as a darker pass on the mood/tone/lighting but it didn't hit the mark. I was definitely channeling ' post apocalyptical genre nature returns' vibes from a variety of popular media.
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