Bitom's House Rule Thread - d20

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Bitom's House Rule Thread - d20

Post by Bitom » Fri Jan 28, 2011 9:32 pm

Vardaen wrote:Group Stealth/Perception Checks
Games: 3.5, Pathfinder, WoW

I quote from a PM from Trogdor
Any time you require the entire group to make successful Stealth checks you're basically saying that the group will be discovered. Even assuming that everyone has a halfway decent Stealth check (which we know isn't the case), the odds that at least one person will roll poorly is extremely large. For example, with six people rolling, there's an 82% chance that at least one will roll a 5 or under. In fact, with four people rolling, there's a better than one-in-four chance (26%) that at least one person will roll a "1".

Add to the mix that they only have to make one of multiple rolls, and it gets even worse. Although if only one person were making a Perception check, the chance of rolling a 6+ is only 75%, it jumps all the way up to 94% when two of them get to make the roll.

Basically having a roll off between two groups where the first group takes the worst roll (Stealth) and the second group takes the best roll (Perception) basically means that the group that takes the worst roll loses an overwhelmingly large number of times.

FWIW, the way I tend to do things if people are trying to hide as a group is to pick the best Perception bonus in the perceiving group and the worst Stealth bonus in the hiding group. Everyone else can make an Aid Another check to help in the respective rolls. That has the benefit of making it likely that a group with a bad low Stealth roll will be found, but not guaranteed.

Say you have Stealth checks of +2, +4, +4. +7, +10, and +13, and Perception checks of +6 and +6.

You'd have a base +6 Perception check against a +2 Stealth check. The Stealth check would get probably 3 successful Aids, and the Perception check might get 1. That would give a +8 versus a +8, even up. That you'd succeed or fail. And that seems to me more reasonable odds for a game that 95/5.
I shall begin to use this method for setting ambush, using group stealth checks, and the like when a party attempts to hide as a whole group.
this one comes down to realism vs fun. The straight-up "Everybody rolls" method is the most realistic. If you have a guy with 5 left feet wearing heavy armor with bells attached, the group gets caught if even ONE guard forgot his earmuffs. But I agree with Trog. It's not fun to always fail.

Trog's method isn't bad, but I would suggest disallowing the Aid another for those doing the sneaking. It really doesn't make sense. How do you help chucko be sneaky when you're busy sneaking yourself? I think that since the people doing the sneaking are usually going to be the larger group (Guards are spread out with only a few in the area you're trying to sneak past) that Trog's method gives the sneaky group too much advantage (Also true when 10 orcs try to sneak up on the sleeping party with only one member awake.)

I would suggest a modification:

The worst stealth person in the sneaky group rolls. Everyone else in the group is assumed to have gotten more than him. (Think of this as "The party rolls a single die, and everyone's bonuses are applied to that roll individually" if it really matters WHO got heard)

Those who might detect the sneaky group also get one roll. The best listener, aided by whoever's standing near enough to also have detected the sneaky group. This gives you a reason to have a lot of guards, and also gives you a reason to send the thief/assassin ahead of the party to thin them down.

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Re: Vardaen's House Rule Thread - d20

Post by Trogdor » Fri Jan 28, 2011 11:47 pm

I thin Bitom's comments have a lot of merit. In my table top game I tend to use this as a rule of thumb, and haven't had to write it down coherently. I like his modification. It looks like it'll give just the right feel to things.

But I think his best comment is noting the difference between realism and fun. I like to give my players incentives to do fun things. And so sometimes the fun things have a chance of working in the game when they'd be highly unlikely if a dash of realism were tossed on.

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Re: Vardaen's House Rule Thread - d20

Post by Vardaen » Fri Feb 04, 2011 2:02 am

I split this off of my thread, because I locked my thread so I can post offical rules for my games, and so it would get cluttered with conversations about rules.

For my part I 'm not using this at all for Move Silently, only Hide. Why can't one guy move around the group and cover them off, add branches, push their heads down, etc. Makign the group as a hold harder to see. I'm not sure why armor makes you easier to see anyhow.

Bring green leather armor in in afield of snow is apparently easier to hide in than a set of white painted plate mail is :)

Anyhow, sneaking, scouting, moving silently, that's all still goign to be normal in my games, but if the group gets time to hunker down and hide from sight as a group to set and ambush, this rule applies in my games,.
"He that breaks a thing to find out what it is has left the path of wisdom." - Gandalf
J.R.R. Tolkien, Council of Elrond, The Fellowship of the Ring

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