CONCEALED
A creature can be hidden at different For example, most creatures use sight so "obscured from view" would give most attackers disadvantage. However, if a creature had blind sight (echolocation), they could still attack the target normally. If a creature had an effect that "obscures sound" then it would effectively negate blind sight (echolocation) or if it had an effect that "obscures smell" then it would negate blind sight (scent) and so on and so forth. Obscuring blind sight automatically obscures blind sense of the same type as well.
- Concealed 1 (Obscured): Attackers suffer a penalty to attack rolls and Perception checks against you equal to double this condition's value unless they have an acute sense that's unaffected by your concealment.
- Concealed 2 (Invisible): Attackers know where you are, but can't see you.
- Concealed 3 (Hidden): Attackers know you're present but don't know where you are. They'll likely search for you or attack at random trying to find you.
- Concealed 4 (Undetected): Attackers don't know you're present and won't intentionally or knowingly target you.
Typically GMs determine if a creature is detected or undetected using secret rolls (usually Stealth and Perception).