So the shadow barbs spell states that "The chain radiates darkness in a 10-foot-radius spread around you, reducing the illumination level in this area by one step, but not below the level of dim light." Deeper darkness lowers the light level by two steps. The former does not indicate that it doesn't stack with other darkness effects, while the latter only states that it does not stack with itself.
What happens if these two spells meet in an area of bright or normal light? Shadow barbs drops the ambient conditions to normal and dim respectively--fine so far. But then deeper darkness lowers the lighting from there to dark and magically dark, respectively. So would that cancel the effect of shadow barbs and put the light back up to dim and dark respectively, because shadow barbs doesn't lower the light levels below dim? Or do they stack because shadow barbs isn't actually lowering the light level below dim--it's deeper darkness doing that? Or is there RAW that explains all this away that I just missed?
