Heavily Obscured
A heavily obscured area-such as darkness, opaque fog, or dense foliage-blocks vision entirely. A creature effectively suffers from the condition=blinded condition when trying to see something in that area.
Appendix D: Rule References / Rule
A heavily obscured area-such as darkness, opaque fog, or dense foliage-blocks vision entirely. A creature effectively suffers from the condition=blinded condition when trying to see something in that area.