On page 26 of the DMG, it describes a passive insight check and gives an example of using it in a social encounter. Could you help me with it and how to use it? Step by step would be appreciated
[RPG] How to use passive insight checks
dnd-4e
Related Solutions
Some optimization, since the other answers cover the negative case well...
For stealth, consider "The rules of hidden club" as a fantastic discussion on how stealth actually works in D&D. You also cannot make a stealth check to hide at the beginning of an encounter because you're not a gnome nor have you taken a move action.
The trick you're looking for is shadow walk + cunning sneak for perma-stealth. Or, to allow for your specific goal, shadow walk + hidden sniper give gives you CA any time you have concealment.
You can get cunning sneak through hybrid talent, and shadow walk through accursed shadows. You may also want to consider the level 10 utility persistent tail.
Edit: Working off the "how can I optimize this" part of your question, I recommend:
====== Created Using Wizards of the Coast D&D Character Builder ======
Drisdahun, level 6
Pixie, Rogue|Assassin
Fey Beast Tamer Starting Feature: Fey Beast Tamer Companion (Young Owlbear)
Hybrid Assassin: Hybrid Assassin Will
Hybrid Talent: Rogue Tactics (Hybrid)
Rogue Tactics (Hybrid): Cunning Sneak (Hybrid)
Background: Silent Hunter (Silent Hunter Benefit)
FINAL ABILITY SCORES
Str 8, Con 13, Dex 20, Int 10, Wis 10, Cha 18.
STARTING ABILITY SCORES
Str 8, Con 13, Dex 17, Int 10, Wis 10, Cha 15.
AC: 21 Fort: 15 Reflex: 20 Will: 19
HP: 44 Surges: 7 Surge Value: 11
TRAINED SKILLS
Perception +9, Dungeoneering +8, Streetwise +12, Stealth +16, Thievery +13, Bluff +12
UNTRAINED SKILLS
Acrobatics +8, Arcana +3, Diplomacy +7, Endurance +4, Heal +3, History +3, Insight +3, Intimidate +7, Nature +5, Religion +3, Athletics +2
FEATS
Level 1: Hybrid Talent
Level 2: Student of Malediction
Level 4: Cursed Shadow
Level 6: Ki Focus Expertise
POWERS
Hybrid at-will 1: Sly Flourish
Hybrid at-will 1: Executioner's Noose
Hybrid encounter 1: Shadow Darts
Hybrid daily 1: Targeted for Death
Hybrid utility 2: Cloak of Shades
Hybrid encounter 3: Low Slash
Hybrid daily 5: Compel the Craven
Hybrid utility 6: Pixie Invisibility
ITEMS
Bracers of Archery (heroic tier), Scavenger Bird Ki Focus +2, Hand Crossbow, Shadowdance Leather Armor +1, Collar of Recovery +1, Adventurer's Kit, Rapier
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The first mistake is combining melee and range. While it works in theory, it's very hard to pull off in practice. The cunning sneak, shadow walk combo is solid, though a touch gimmicky.
Here, you flit around the edges of the battlefield and drop sly flourish while you build up sufficient shrouds on your primary target, then you drop your nova-encounter.
Ki focus powers all of your attacks so you save on implements. Pixie flight will come in real handy and be a fascinating way to play through the game. As a ranged scout/striker who is tiny, you'll have all kinds of out-of-combat fun as well as in-combat. At the same time, your fey beast will provide a meatshield in combat so that you're not placing an undue load on your defender or leader.
DPR of this build:
`Sly Flourish: +13 v. AC / 1d6+13+2d6 = 80% accuracy, .75*(d(3,6)+13+2)+.05*(3*6+13+2+d(2,6))=21.12 = 3.40 round striker. Not particularly good, but above the 4 threshold so it works, especially with the stealth assets you bring.
And then you can dump 2-4 shrouds whenever appropriate on another mob, and then open as appropriate.
With more thought, I realized we were overthinking this. In the build above, you were using this whole complicated edifice to power stealth for combat advantage.
With the thief guide:
====== Created Using Wizards of the Coast D&D Character Builder ======
level 6
Drow, Thief
Fey Beast Tamer Starting Feature: Fey Beast Tamer Companion (Young Owlbear)
Background: Born Under a Bad Sign (Born Under a Bad Sign Benefit)
FINAL ABILITY SCORES
S tr 8, Con 13, Dex 20, Int 10, Wis 10, Cha 16.
STARTING ABILITY SCORES
Str 8, Con 13, Dex 17, Int 10, Wis 10, Cha 15.
AC: 22 Fort: 15 Reflex: 21 Will: 17
HP: 57 Surges: 7 Surge Value: 14
TRAINED SKILLS
Stealth +15, Thievery +13, Athletics +7, Acrobatics +13, Bluff +11, Perception +8, Insight +8
UNTRAINED SKILLS
Arcana +3, Diplomacy +6, Dungeoneering +3, Endurance +4, Heal +3, History +3, Intimidate +8, Nature +3, Religion +3, Streetwise +6
FEATS
Level 1: Crossbow Expertise
Level 2: Backstabber
Level 4: Ruthless Hunter
Level 6: Two-Fisted Shooter
POWERS
Lolthtouched: Cloud of Darkness
Thief utility 1: Tactical Trick
Thief utility 1: Acrobat's Trick
Thief utility 2: Fleeting Ghost
Thief utility 4: Sneak's Trick
Thief utility 6: Chameleon
ITEMS
Rebounding Hand Crossbow +2, Magic Leather Armor +2, Bracers of the Perfect Shot (heroic tier), Hand Crossbow, Amulet of Protection +1
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We get what you were working towards. First, with tactical trick, you get combat advantage against... anyone adjacent to an ally. You also get your full move with limited OAs, so you'll probably be able to find cover. With crossbow expertise, you ignore cover and superior cover and with two-fisted shooter you reload as free.
Therefore, every turn you can attack with CA, not dependent on a stealth roll.
Your DPR, counting your owlbear (who counts as an ally, BTW, and who can move when you take a move action, meaning you can target anyone you like with tactical trick): `+14 v. AC, 85% accuracy (counting perma-ca), 1d8+11+2d8 damage. with free RBA on crit) = 24.80 DPR. 2.90 round striker which puts you into the big leagues. With 2 uses of backstab and one rebound you'll hit every single turn (almost), and your DPR creeps ever higher.
You also get the stealth advantages from your build from sneak's trick, allowing you to sneak through deserted corridors (counts as cover) with impunity even if one enemy sees you because of chameleon. The melee version of this is even better due to the charge chassis it is built upon, but it doesn't seem the build you're trying to go for (and is sooo bloody boring).
In and of itself, a bird on a roof is not something out of the ordinary, and not something that would (or should) alarm a character.
I assume from the fact that you are asking the question, that by noticing the bird, and divining its purpose, the character can gain some advantage in the near future.
So to me, this isn't even a perception question, but an insight one - I would let the bird be seen, almost automatically, but only address its significance if the PC passes a passive (or active) insight check.
I would ask the player if they are keeping an eye out for trouble or anything else in particular. If they claim to be, ask for details of what they are looking for, and then give answers appropriate to the questions that are asked.
DM: You proceed down the path towards the building. The light of your lantern illuminates the way ahead, but darkness pervades on either side of you. Do you make right for the building, or do you want to play it safe a study your surroundings?
PC: Play it safe of course. What do I see?
DM: Well, there are some trees on your right. You hear the rustle of what might be wings of a small bird pass overhead. Are you looking for anything in particular?
PC: Well, am I sure the noise is just a bird and not something bigger? Do I see or hear anything threatening?
DM: You're not totally sure about the sound, but you don't see or hear anything threatening.
...
If your players are going to feel betrayed when the significance of the bird is sprung on them, have them hear a bird call as well as the bird above, and then if they ask about birds, let them see the one on the roof, and maybe another in a tree.
If your players don't go for the idea of player skill (embodied here by the need for the players to divine that birds are significant), then a similar scene can be played out, bringing passive insight (or perception) into play by giving out details if their passive score beats a medium or high difficulty for their level.
Picture a suspenseful scene in a film - as the viewer you would expect to be aware of the birds before they are meaningful, but you would either not expect to know the role they have to play, or not expect to know which bird it is you need to focus on unless you have already learned the significance of birds.
As for what to compare the PC's active or passive perception or insight against, the Rules Compendium p126 has the difficulty class by level chart.
I would suggest that this is medium or hard to detect (as significant) for a low level character - so I would pick hard for level 5, which is a target number of 22.
Best Answer
The passive insight check is not something that is rolled or actively used. It is more like armor class or a reflex defense, a number which the opponent must beat to successfully deceive the character. As such, there is no retrying, just as there is no retrying an armor class or reflex defense.
It is, from a gameplay perspective, a tool to speed up the game and reduce randomness. It's basically the assumption that a character takes 10 on their insight checks on these situations. Beyond that, it assists the DM because calling for insight checks is a sure way to make the PCs realize something is up.
It's the same deal with passive perception, except that's used to stealth rather than deception.