Small summary: The octopus model was sculpted in Blender and the scene was rendered using texture and normal mapping, Disney BRDF, volumetric path tracing and two homogeneous media (particles in water and smoke).
Final Rendering

Small summary: The octopus model was sculpted in Blender and the scene was rendered using texture and normal mapping, Disney BRDF, volumetric path tracing and two homogeneous media (particles in water and smoke).