Thoughts on Stealth and Perception in Dungeons and Dragons 4th Edition

I have always had a bit of a problem with perception in role playing games. One issue is the fact that, with so many players (five or six for most games I have run), one player will inevitably roll high and thus find whatever it is they are looking for, even if they have a low score in perception. The RAW for D&D 4th Edition tries to avoid some of this by using Passive Perception Checks.

Perception Rules from the Player’s Handbook

Make a Perception check to notice clues, detect secret doors, spot imminent dangers, find traps, follow tracks, listen for sounds behind a closed door, or locate hidden objects.

This skill is used against another creature’s Stealth check or against a DC set by the DM. In most situations, the DM uses your passive Perception check result to determine if you notice a clue or an imminent danger.

Perception: No action required—either you notice something or you don’t. Your DM usually uses your passive Perception check result. If you want to use the skill actively, you need to take a standard action or spend 1 minute listening or searching, depending on the task.

Opposed Check: Perception vs. Stealth when trying to spot or hear a creature using Stealth. Your check might be modified by distance or if you’re listening through a door or a wall (see the table).

DC: See the table for DCs when you’re trying to hear or spot something, searching an area, or looking for tracks.

Success: You spot or hear something.

Failure: You can’t try again unless circumstances change.

Searching: When actively searching an area or looking for something specific, assume you’re searching each adjacent square. The DM might allow you to do this as a standard action, but usually searching requires at least 1 minute.

Discussing Perception and Stealth

Passive Perception is an interesting idea. It means that players who have high Perception scores will see things which players with low scores will not. However it does also mean that players can never get lucky and notice something, and a DM can easily decide if they want the players seeing something or not by simply setting the DC at a level that is either above or below their score.

In a way, for me at least, this almost makes the whole idea of perception rather pointless. The only time it seems that there will be some question as to what players will or won’t find is when the DM is running a pre-made adventure of some kind. Otherwise all will be pre-determined during the creation of the adventure.

Often in my game I fall back on the old idea of asking players to roll Perception. This is partly because I like the randomness of it, partly because I am old and a bit stuck in my ways and partly because I am too lazy (or perhaps disorganized) to write down all of their passive scores and keep track of them. Some DMs would roll the players’ Perceptions for them even in 3.5 games (or other non D&D games where Perception is determined by some sort of die roll) so that players don’t know that there is something to see. This sort of makes sense but I have never liked rolling for my players. I have always simply hoped that players will be good role players and not act on out of game information. Certainly this isn’t always going to happen but I work with a pretty good group and often the other players will help me out when they see one of their own trying to act on information they do not have, informing the player that they cannot take the action they want to take. Besides my dislike of rolling for my players I have always enjoyed the ominous feeling that creeps over them when they fail a Perception check.

One of my players, Tom Kandris (the guy responsible for my owning copies of the new D & D books), is running a game of his own and has been working on a few House Rules that I wanted to share with anyone who is interested. I had asked Tom if he wanted to do a guest post about his rules but he didn’t feel he was so much “with the words” and instead sent me a summary that I have edited only slightly. Below, mostly in his own words, are TK’s House Rules for Perception and Stealth.

Stealth and Perception from the Mind of Tom

I found it kind of silly how Stealth and Perception currently work in Dungeons and Dragons 4th edition. Too often a bad Stealth roll would do in a player who should be good at sneaking around and I wanted rules that would better show off the players who were good at such things, while still hindering those who were not.

I created a passive stealth number for characters who want to sneak around based on 10 + their Stealth Skill (as would be expected). If an opponent’s passive perception is equal to or higher than your passive stealth, both roll their skills. That means a skilled guard is capable of doing his job and a skilled thief can sneak when they have to, or at least have the potential to.

I also felt there should be a difference between a guard who is “on watch” and a guard that is sitting by a camp fire having a smoke so I worked out some basic modifiers. If an opponent is actively guarding a place or person and thus is actively looking out for trouble, they would gain a +2 to their passive check, though not to their actual roll.

I also changed the way passive perception works. Instead of a character with a passive perception of 20 or 25 automatically finding something if the check to find it corresponds to their passive check, passive perception lets you detect that there is something strange with the room, corridor or area in general. The character could them inform others and they could than roll their perception skills to see if they find whatever was odd. If they fail you could give them additional rounds to detect what they saw if it fits the encounter.

Analyzing Tom’s Rules

Interestingly Tom’s rules were originally based on his assumption that both parties in a RAW Stealth v. Perception situation would be rolling dice. It seems to me that this is inaccurate and only the Stealthing party would need to roll and that roll would be against the passive Perception of the other party.

Still, even knowing the above, Tom’s rules are interesting in that they allow a DM to easily determine whether rolls are needed or not. Of course, this is essentially the Stealth participant taking 10 and the Perception participant acting under RAW and then if the 10 is not enough giving the Stealther another chance to avoid detection. So, if I am reading both the RAW rules and Tom’s rules correctly, the primary change here is to make Stealth a bit easier as some Stealth checks become automatic while others result in a roll. Of course, since both parties roll if there is a roll, the actual roll will see more variation than in the RAW.

For me, I like Tom’s rules more for situations where the players need to attempt to perceive something than when the players are doing the sneaking. They allow only the players that have decent Perception scores to attempt to see the person or group which is sneaking up on them. Of course, there are also modifiers for larger groups that could come into play but hopefully these rules could help prevent the situations where everyone rolls and thus only one player needs to roll well.

I offer these rules because I find them interesting. I’m uncertain if they are necessary but I would love to hear from some of Tom’s players who have experienced these rules first hand. In the end they are probably more appropriate than the rules I was using which essentially called for rolls all the time to determine if something was spotted or not.

Feel free to chime in on this, especially if you have used any modified rules for Perception and Stealth!

    ojiepat Says:

    I like the passive stealth because I have had serious problems in the past with rolling stealth, if you are sneaking near a group of drunks, there is still a significant chance that one of them will see you if you roll low. I’m trained in this, I think I could do well enough to keep drunks from seeing me.
    How many times has our rogue been caught because he tried to sneak and rolled a 1. Tom’s system assures that an undead puppet wouldn’t even get a chance to try and see the skilled stealth person. It just feels more accurate to me.


    Of course, one of the complaints about Passive Perception, related sort of to your problem I would think, is that 50% of the time Passive Perception is better than active Perception.

    jim Says:

    i like the way tom runs the game. it helps speed things up. and the descriptions he gives to the high passive perception character are good. it adds a sense of instinct or “gut feeling” to the game. the player may not know what is wrong, but they “sense” it.

    as for the base ten plus skill score. that’s no different then taking 10 in most circumstances. so that’s not a bad way to look at it. the character still has the option of actively trying to hide. which at that point a roll is made. it makes the game fun, and fast. both of which are a good thing.

    the house rules also allow experienced characters to stealth past or ignore encounters that would slow down. all in all tom is a great DM. and the games are something to look forward to.

    Pierre Says:

    Joining the discussion late.. but the problem is the D20 system. it’s too random. you need a xDy system to make a nice bell curve.

    Dylan Says:

    Perhaps instead of using the D20 system use something similar to what Pierre said. xDy vs zDy.

    y is a small die, D4 or D6.
    x is the perceivers perception skill.
    z is the sneakers sneak skill.

    So someone with a sneak skill of 9 would roll 9D4 with a minimum roll of 9, and someone unskilled in perception (or the drunk guy at the bar) might have a perception skill of 2 or less after modifiers, their maximum roll would be 8, so they could never beat the person attempting to sneak.

    This would allow trained players to be consistently better than untrained players without having to use passive scores or the variability of a D20.

    Basically, if your skill is theirs times 4 you always win.


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