I couldn't sleep this morning, on account of the temperature and pressure change out here and the inflammation it induces; so I got up, slammed a naproxen, and did the one thing I still felt capable of. This took maybe two and a half hours to produce. The mushroom glow was done by wiring emission strength to a channel of vertex color, and literally painting it on. Its animation is a basic hue rotation of the emissive color, wired to the frame. Afterward, it was tied to a stretched out gradient noise, which was also wired to a bump node to give it some additional texture. A similar process was done with the dimly lit log, with an additional layer of Musgrave gradient noise forming the boundary between the bark and the moss on it.
The water wasn't that complicated, it's simply another Musgrave gradient noise, tweaked to my liking, tied to an offset animated with the frame number. While its shape distortion isn't especially visible, you can clearly pick up on it in the reflections of the mushrooms.
The distribution of the mushrooms over the mound was managed by geometry nodes and some weight painting to manage their density; I also tied that, after some tunable math, to the scale of the mushrooms. The same was done for the plants. For the sake of keeping things simple, and since I don't have immediate plans to use it outside of Blender, they're just instanced geometry; but, in the future, it's easy enough to realize them.
It took me maybe 2½ hours to do, not counting rendering time. The whole thing is about 36,755 faces, but that could probably be dropped dramatically with a little decimation, if I needed to. It may be biased, I'm not 100% on whether Blender considers every face in an instance, or just the original; but by modern standards I think it's pretty good. Also, I'm not feeling inflamed anymore, so go naproxen!