I wanted to do a low poly cozy fantasy diorama, of a sunny spring day. There is a well, a bench, some fluffy trees, grass, cloves and flowers on the ground, a nice stone path with weight paint and two lampost with a soft emission and soft lights under them. I used an HDRI in the World background and align the sun light to the HDRI light and played with glare. Made on Blender, using Cycle render.

Then, for the same scene elements, I modify the HDRI background to a gradient, unsed a Volume for a fog and a moon on emission + light for the main light. Some fireflies with very strong green emission and leaves, grass and mushrooms on the ground. The lights under the lampost is also stronger, and there is some secondary ambiant lighs in greenish color to reinforce the spooky aspect.