Stealth Mechanics

[Franko Tyrador]

Long time player and GM (who's always getting stumped by Vek), how do you guys handle stealth checks vs active perception checks. D20 can easily convert to %, that's easy, but, do you then subtract the players prowl skill from the perception, the perception from the prowl, etc?

[kiralon]

MIne is a bit modified, perception is a stat for me like ps or pp and is rolled when the character is created (same with willpower and luck).
If someone is sneaking they make a prowl check, and the spotting party makes a perception check, the prowling person gets a direct negative of 5% per point below the spotter perception on a d20 (detect ambush is similar) and this is rolled for each spotter so if one person makes the sneaky person fail his prowl check, and another doesn't then only one of them sees him, and i have perks and skills that add bonuses to both. I also have environmental modifiers that add bonuses and negatives to both.

[ShadowLogan]

Well According to Rifts Ultimate Edition main book (pg368), Perception vs Skill is handled by converting the skill from a percentage into a D20 bonus (+1 per 10% round down) and then having a D20 vs D20 roll off (D20 + Perception bonus VS D20 + Skill Bonus) with the high roll winning.

[GoliathReturns]

As Logan said, there's a RUE way of handling it.

Myself, because I've been doing it for PF longer than than the RUE book was out, I houserule it.

Perception= d20 + IQ bonus or ME bonus, whichever is higher.

Contests-
Perception check VS
Prowl, for example- successful skill check gives a +1 for every 5% "clearance" (ie, you have the skill at 45%, you rolled 20, that gives +5 on the d20). I'll often also allow a PP bonus on the d20 contest.

If the person is actively looking, and not just passively, I'll give them some sort of bonus as well.

Why? Because it's easier to hide vs someone's passive looking than it is to see someone by only passively looking.

--
GS

[Library Ogre]

You might also borrow from Hackmaster: d100+Prowl skill % v. d100+Perception %

[Veknironth]

Well, I'd do it where if the prowl is successful, then that's that. If the person fails, then you can roll a perception. I figure you can either do a straight roll, or take the amount by which you missed the prowl roll as a modifier.

-Vek
"I think you mean you have been delighted by the excellent role playing I do."

[Mogge]

I do neither of that actually.
I give the prowler modifications based upon the difficulties such as the ground is wet, if the area is actively watched, light etc etc. So the Prowler is the only one making the roll. If successful - great, if not - great, prepare for combat!
The modfications can sometime be daunting, especially if trying to sneak during daytime through a corridor where people passes - most characters can´t succeed with that and thats OK.
Makes everything much faster as well, just the one who are using a skill that makes a roll - nothing oppose other than modfications.

[Soldier of Od]

Well, I'd do it where if the prowl is successful, then that's that. If the person fails, then you can roll a perception. I figure you can either do a straight roll, or take the amount by which you missed the prowl roll as a modifier.

-Vek
"I think you mean you have been delighted by the excellent role playing I do."

I was just about to post something very similar!
I never saw the need to create a "contested roll" - if you make your prowl roll that's all good, but if you fail, you have made a noise (or whatever), and then the people around need to roll perception to see if they notice the noise. The perception difficulty target, like all perceptions, would be set by the GM based on the current circumstances, which could include how badly you failed the prowl roll.
I partly do it this way because, in Palladium, prowling is really hard to do , and I think it is fair that, if you accidentally step on that twig, there is a chance that the bad guy doesn't notice it.

[kiralon]

I do it as my players didn't like the bad guys suddenly appearing behind them and gutting them because they couldn't parry or dodge an unknown attack from behind, so for me its more the players than against them, as the average enemies perception isn't high, and the modifier goes both ways, so if the enemy roll badly the players can technically fail their prowl roll, but the enemy still doesn't notice them because the enemy is more oblivious than they suck at prowling.

[GoliathReturns]

I'm with Kiralon for a reason for the contested roll.

It just never sat right with me that the opposing side has no chance to notice anything, unless the sneaker flubs his check. Especially at high levels, when you have someone that's sneaking around at 85+%.

--
GS

[Franko Tyrador]

Thanks folks, gives me some things to think about.

[Soldier of Od]

I guess for me it stems from the fact that there is (still) no perception mechanic in Palladium Fantasy, which is the game we played the most for years. When Nightspawn came out and introduced perception rolls, we immediately introduced them to our Palladium Fantasy games, but to be honest, we missed that note under perception rolls about opposed checks, until someone pointed it out here on the boards. So we had played for years before becoming aware of this new rule.

When we did see the rule in RUE, it never sat right with us - I never liked the way prowl was singled out as the only skill that someone else can ruin for you, even if you roll a success. If I pick a lock, the lock doesn't get a roll to stop me picking it. If I successfully roll for fishing, the fish doesn't get a roll to cancel out my success. As I said, prowling is very difficult to achieve - it starts at only 25%; to reach the dizzying heights of 85% mentioned by Goliath returns, most characters would need to be level 13! Even the best prowlers, thieves or assassins, only get a measly +10% to prowl, so would have to be 11th level to reach 85%. Should an 11th level assassin have a good chance of sneaking up behind you unnoticed? Hell yeah! A 4th level thief still fluffs their attempts at moving quietly half the time! I don't want to hinder that even more.

And that is only if the prowler is alone! If you want to stay unnoticed, you probably shouldn't be hanging around in large groups, but if even only two or three people are prowling together, the chances of someone failing a roll are very high. Add a perception roll on top of that and it is a virtual certainty. A pair of mid-level thieves may as well quit crime and go straight.

But that is just my opinion, anyway, and clearly it works well for others, so everyone do what works for you!

[ShadowLogan]

When we did see the rule in RUE, it never sat right with us - I never liked the way prowl was singled out as the only skill that someone else can ruin for you, even if you roll a success.

Technically Prowl was not singled out in the text of RUE (pg368, emphasis in text): "Perception Rolls vs Stealth & Concealment Skills: A number of skills, among them Prowl, Detect Ambush, Detect Concealment, Camouflage, and Concealment, have an impact on Perception Rolls." (I don't have Nightbane/spawn when it was introduced so I can't say anything about the text that appears there).

Now it is true when the presented example in the next paragraph, Prowl was the only skill considered in the scenario but that is a lot different than being the apparently only successful skill roll that can be ruined as you present it. Megaversally I have experienced the opposite, where a successful attack roll was ruined by a skill check (1E RT & Macross2, the way the groups I played with handled piloting maneuvers essentially amount to D20 vs D100, even if the D20 was successful it would be superseded by a successful piloting check unless the D20 was a nat 20 ((always hits)). Now I don't know if we played it correctly, those main books never really gave examples of it in use so this might be the result of a "house rule" situation).

[Franko Tyrador]

S of Od - good explanation. i like it. last game i did it something like your way, with a twist... if they succeeded at their prowl check, they were good to go; if they failed, the enemy got a perception check.

[Mogge]

As I have understood it, this is not a game where opposed rolls have existed nor should exist.
Thats why, when you are prowling for instance, the GM take into account how hard it should be; are the guards on alert?, are there any good "hiding spots" along the route? how´s the illumiation? etc etc. From there the GM gives a modifier that is applied to (much like understanding alien tech and their modifiers) the prowl-skill. Then the Prowler rolls.

[kiralon]

It has the most opposed rolls of any game i know, because most of the time when someone hits you, you get to parry/dodge/roll with punch etc.

But I do it on certain skills to prevent this from happening to the players.

[Soldier of Od]

Technically Prowl was not singled out in the text of RUE

True - I missed that there are other skills mentioned as well.
I don't know Robotech/Macross at all, so I can't comment on that example.

[Soldier of Od]

It has the most opposed rolls of any game i know, because most of the time when someone hits you, you get to parry/dodge/roll with punch etc.

But I do it on certain skills to prevent this from happening to the players.

Ha ha! Very good, but I think in that particular case, the penalty to the attacker's prowl roll would be extreme!

[Mogge]

It has the most opposed rolls of any game i know, because most of the time when someone hits you, you get to parry/dodge/roll with punch etc.

Im sorry, should have said no oppose rolls on skills. Combat is of course another beast and would be less fun without all the special things one can do inside a combat.