It's in the Rhythms of Play part of the PHB which is essentially players tell the DM what they want to do and the DM narrates what happens, typically using dice rolls when the outcome is uncertain.
Even stepping out into full view for an attack during combat between a 4-man party and enemy guards, the DM can use Perception to determine if each enemy sees the PC. The Hide action says "Make note of your check’s total, which is the DC for a creature to find you with a Wisdom (Perception) check" Most--including myself--took that to mean you need to take the Search action (partly because of a Treantmonk video, partly because of the Search action description) to find an enemy, but RAW, it only says a Perception check. The DMG says you (or DM) can call for a Perception check when a creature is using Stealth to hide, so the DM can just roll Perception for the enemies; if one makes it, the gig is up, but if all fail you get your one glory stealth attack in the fight with advantage, and you lose the Invisible condition right after
Yes in combat stepping out and attacking I feel should be at advantage, whether you get advantage because they didn't see you approach them or because your sudden unexpected appearance has caught them flat footed and vulnerable is basically irrelevant, you get advantage on the first attack and are seen.
Fair enough and thanks. I would never require the Seach action (the bolded part) because that is what Passive Perception is for IMO in this case.
I never said anything about passive perception. The DMG (p.35) says this, which is also on post #549:
Using the previous scenario, the DM can make the call to run an active Perception check (instead of the Search action) for the creatures to detect the player that's out in the open on the player's turn. Why? Because the text in the Hide action doesn't say "take the Search action"; it only says a Perception check, and if you step out in the open then it's fair game.
My interpretation has always been making an "active" Perception check IS the Search action. Passive Perception, on the other hand, is used for either (a) routine Perception (such as a guard on patrol) or (b) notice without consciously trying, and is used when it isn't your turn.
Correct. That is why I use "active" Perception as the Search action. It is your turn and you are spending your time looking. It is the only time you roll.
Since rolling will more often lead to a worse result than Passive, I go with Passive. I don't think either is "incorrect", but probably explains our different views.
Here is what the DMG says about Passive Perception, though that's not to say it's the only thing it can be for: Sometimes, asking players to make Wisdom (Perception) checks for their characters tips them off that there’s something they should be searching for, giving them a clue you’d rather they didn’t have. In those circumstances, use characters’ Passive Perception scores instead.
True, but for those creatures that have low passive scores, it might be better to take the chance with an active roll, specially if you want to challenge the PC's Hide action
As a note the DM is by RAW supposed to be in charge of when a PC can attempt to hide, so there's an argument that says you can't attempt to hide at will until you you hit that DC 15. Instead players who chose to stealth when there are no potential hostile creatures nearby simply don't roll until it actually matters.
Sure, but I'm talking about a player Hiding, so this is irrelevant as it is the creatures who are opposing it.
And on their turn, if they use the action to Search, I would.
Well, you aren't hiding unless you make the DC 15 check. So, if you are behind total cover or whatever, and a potential hostile creature approaches and you roll then, does a failed roll mean you don't Hide and the creature knows about you? Or what?
You aren't hiding unless the DM says you can take the hide action, and they can if they want, decide you can only take that action right before it's going to actually come up.
