Rising Waters
Here's an illustration for an upcoming tabletop RPG book. This image started with the idea of a cage suspended from an ornate wrought-iron pole, with some malicious creature left to rot or drown (or both) in a dark space. Everything grew out of that idea.
Balancing the daylight from above with the red fog at the far end was the trickiest part. Maybe apart from getting the water right, combining refraction and algae murkiness.