I've come across a tricky situation as a player regarding the Alert Observant feat.
Among some other features, this feat grants passive advantage on Intelligence (Investigation) checks. Meaning, a character with this feat has a passive Investigation score of 10+Int Mod+5+Proficiency (if applicable).
I'm playing a Wizard in a game and chose to take this feat. With the above math, I have a Passive Investigation of 20. My DM is kind of new, and is struggling with how to handle this ability. I've given him my thoughts and feedback (what I would do if I was the DM), but in the end, its his call to adjudicate this ability.
Any thoughts or feedback from the Hive Mind?
Sorry all, not the Alert feat. The Observant feat.
Well, there's a few ways to go about this. Let's start with this tweet from Jeremy Crawford, the one we all go to for Sage Advice:
Passive Perception is an option that a DM chooses to use or not. If you use it, Perception checks are typically made only when characters actively search for something, and normally, they're searching because their passive Perception failed to notice something.
Investigation is pretty much the same way, only doubly so. You can't investigate something you haven't seen yet. So, if it's something hidden, your Investigation skill won't help you any; you'll have to Perception perceive it first. Or have someone else point it out to you.
Next, Crawford also has this advice on passive investigation:
Passive Investigation is a tool for the DM who wants to see if a character notices a clue, without asking the player to make a roll.
And the PHB has this to say about the investigation skill itself:
When you look around for clues and make deductions based on those clues, you make an Intelligence (Investigation) check. You might deduce the location of a hidden object, discern from the appearance of a wound what kind of weapon dealt it, or determine the weakest point in a tunnel that could cause it to collapse. Poring through ancient scrolls in search of a hidden fragment of knowledge might also call for an Intelligence (Investigation) check.
And in the 27 Apr 2017 episode of Dragon Talk, in Sage Advice, Crawford describes passive perception as follows:
The passive perception score represents the minimum, the baseline, of your awareness. So anything or anyone trying to Stealth check upon you has always to overcome your passive perception score. Even when you decide to make an active Perception check, and that roll + modifier is lower than your Passive Perception score, the Passive Perception score still counts as the DC to overcome for a Stealth check. Making an active Perception check means that you want to try to "beat" your Passive Perception score, and hence try to increase the DC for a Stealth check. This is true for both combat and non-combat situations.
So, what should we take away from all this? Your passive investigation score may give you clues for free, without you, as the player, having to roll the die to see if you piece them together, if the DC for the investigation check is equal to or lower than your passive investigation. However, from the DM's side, this doesn't mean they are compelled to give you any and all clues that are available to you without you having to roll a check. It's a tool for the DM to use if they want to.
But that's just a meaning. My advice to your DM is to make use of your character in the same way that you might use NPCs: on occasion, your character has some bit of information that is necessary for the party to proceed, or to proceed more effectively. Especially when the players are having a rough time figuring something out. Players have been spending the last hour trying to piece together this puzzle? Your character gives them a hint. ("I think we should start by rotating the wheel to the left. That seems to have done something each time we've tried.") Your party is trying to get to the bottom of a murder mystery? Your character understands something the players don't. ("Y'know, if the lord's nephew was killed in the garderobe, if something was dropped down the chute during the murder, it might have washed downstream. Maybe we should check there.")
Making use of the Observant feat in this way does a couple of things for the table: first, it makes the PCs more important. They are the ones figuring things out, not the random NPCs giving them information. Second, it makes the player feel like they didn't make a bad choice with that feat. If a feature never has the opportunity to be used in an adventure (like having a ranger with a favored terrain of "arctic" when you're playing Waterdeep: Dragon Heist), it feels like a bad choice. Without making good use of the passive boost to both perception and investigation, all you get is the ability to read lips and a +1 to intelligence. Might as well just do a +1 to int and a +1 to some other ability score.
Ultimately, though, you already said the right answer: "in the end, its his call to adjudicate this ability." As Crawford said of passive perception, your passive investigation "is an option that a DM chooses to use or not." While I may think it's a bad call to not make use of it on occasion, as long as the game is still fun, that's what matters.
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