The rules for stealth in 5e are notoriously vague. I've been DMing 5e for about a year now, and there's something that's always bugged me about stealth in 5e. We've had several discussions about these issues in my group.
A quick summary of the rules: When someone is trying to hide, you compare their stealth check to the other party’s passive perception or a perception roll, based on the situation. You can normally only hide in lightly or heavily obscured places, depending on your feats and DM ruling. Out of combat, someone distracted could be stealthily approached in broad daylight, for example. Perception is the skill that allows you to notice things, not only through sight, but also through hearing, etc.
Which leads to my actual questions: using sight to perceive objects that are lightly or heavily obscured both imparts a penalty. You get disadvantage on perception checks that rely on sight for the former and you can’t use any skills that rely on sight for the latter, as you’re effectively blinded when looking into a heavily obscured area.
Does this mean that if someone is hiding - since they need to hide in obscured environments - that the person trying to detect them always has disadvantage? If so, this means that stealth checks pretty much always succeed, as a -5 to passive perception is devastating. Or is there no disadvantage because searching for a hidden person does not solely rely on sight but relies on hearing as well?
The PHB Errata state that the question isn’t whether a creature can see you when you’re hiding. The question is whether it can see you clearly. One of my players has argued that this means that you can approach an enemy in dim light out of combat after a successful stealth roll, even if that enemy is looking straight at you, and that this enemy even has disadvantage on his passive perception to spot the player (see question above). Is this truly in line with RAW ruling? Seems a bit strange, as anyone without darkvision should still see someone approaching pretty clearly in dim light.
Thanks in advance!