Question reguarding To Hit probability

[zagman]

Hi guys, new to hero systems and the champions universe. I apologize if this has been brought up before but it is the only thing that bugs me. Been going through the rules and play testing for a while now and one thing jumps out is how easily you can end up with a large difference between the effective OCV and DCV of two characters expecially in champions where super agility and combat skills are rather common making the chances of a hit highly unlikely or almost certain. A difference of only 6 means that there is less than a 5% chance of hitting and a difference of 8 makes it about half a percent or a 1/216 chance of autohitting.

 

What about modding the TH system from a 3d6 into a 2d10 system. Rolling 2d10 gives a range rather close to that of 3d6 while being more evenly distributed without running into the problems that D20 faces. The single d20 system has always bothered me especially where skills are concerned. Here is a little breakdown using common targets.

Result 3D6 2D10 D20

Crit .46% 1% 5%

6- 9.26% 15% 30%

8- 25.93% 28% 40%

10- 50% 45% 50%

11- 62.5% 55% 55%

14- 90.74 79% 70%

 

My main questions are:

What do you guys think of using a 2d10 TH system?

Is there anything in the game that this breaks?

[Alibear]

Re: Question reguarding To Hit probability

 

Very rarely do we need to change the rules just use the ones we have better.

 

What about instead of changing the dice we use we modify the characters so the OCVs and DCVs are closer together thus increasing the chance of hitting?

 

A difference of 6-8 is absolutely massive in Hero. That is like Spiderman going toe to toe with a beat cop or something equally unbalanced.

[Alibear]

Re: Question reguarding To Hit probability

 

Just to be clear - I think the 3d6 bell curve is such a cornerstone of Hero that if you removed it you'd be playing a different game. I doubt too many people here would be happy to lose it either.

[Sean Waters]

Re: Question reguarding To Hit probability

 

I agree: a flatter distribution means that more extreme results are possible, but that is not a good thing IMO: if a six year old child is fighting a pro wrestler, the pro wrestler is going to win, EOS (unless it is a 'Home Alone' type movie game).

[zagman]

Re: Question reguarding To Hit probability

 

Very rarely do we need to change the rules just use the ones we have better.

 

What about instead of changing the dice we use we modify the characters so the OCVs and DCVs are closer together thus increasing the chance of hitting?

 

A difference of 6-8 is absolutely massive in Hero. That is like Spiderman going toe to toe with a beat cop or something equally unbalanced.

 

Just to be clear - I think the 3d6 bell curve is such a cornerstone of Hero that if you removed it you'd be playing a different game. I doubt too many people here would be happy to lose it either.

 

Firstly, I absolutely agree that a bell curve is essential to Hero. That is why I though of a 2D10 roll since it is still offers a bell curve, just a more forgiving one. A difference of 6 is simply a Dex 13 police officer firing at a dex 17 criminal at 18meters or an dex 8 criminal dodging; said cop who is above average would have to fire 21 times to hit said criminal or 2 minutes straight firing; 2D10s make it a 1 in 10. At 34meters that becomes a difference of 8 meaning a 1 in 216 chance of hitting. With 2D10 he has a 3 in 100. There are countless other situations where something like this occurs, but can be altered in favor of playability and/or realism.

 

 

I agree: a flatter distribution means that more extreme results are possible' date=' but that is not a good thing IMO: if a six year old child is fighting a pro wrestler, the pro wrestler is going to win, EOS (unless it is a 'Home Alone' type movie game).[/quote']

I agree, that is why I dislike a D20 system as a whole. Granted a 2D10 roll is somewhat flatter distribution along the bell curve, but it is no where near flat. Of course a 6 year old isn't going to beat a pro wrestler, same result either way. And To Hit isn't the question here since there won't be a large limit on the dex of the child, mainly if the child could damage the adult which they really couldn't. The scenario you provided is less about hitting and more about hurting.

[Alibear]

Re: Question reguarding To Hit probability

 

There are countless other situations where something like this occurs, but can be altered in favor of playability and/or realism.

 

 

Oh oh, he said realism. If you want the 17 dex guy to be realistic give him 3 or 4 dcv and the 4 or 5 ocv cop can still set/brace and hit him with his 9mm.

[ghost-angel]

Re: Question reguarding To Hit probability

 

I just limit the CVs in a game to a tighter range. Only on rare occasions (Drama!) should CVs move too far from each other.

 

8-12 is a good range for Supers I've found.

Or put another way - a Four Point Spread can make the crack shot feel awesome, while still not being a gimme.

[PhilFleischmann]

Re: Question reguarding To Hit probability

 

The basic answer is that all the PCs and major bad guys (not the mooks) shouldn't have that wide a range of CV differences. If the highest is 10, the lowest should be no less than, say 6. (This is a rough guideline only, YMMV.)

 

However, there are ways around this - Area Effect attacks (or Explosions) are great for hitting that hard-to-hit Artful Dodger. Or you can at least make him waste his phases Diving for Cover. Then again there's also Mental Powers which target ECV (MCV).

 

If you want to change the dice rolls, I'd recommend something I've been toying with for a long time - partially because of the exact problem you mention: use "bigger" dice. I recommend 3d12. It preserves the exact same shaped bell curve, only bigger and more granular. The base attack roll then becomes 20- instead of 11-. A Familiarity roll then becomes 15- instead of 8-, and a 14- roll becomes a 25- roll, for example. This way the chances of hitting change by smaller steps. Instead of jumping from 50% at 10- to 62.5% at 11-, you go from 50% at 19- to 56.3% at 20-.

[zagman]

Re: Question reguarding To Hit probability

 

The basic answer is that all the PCs and major bad guys (not the mooks) shouldn't have that wide a range of CV differences. If the highest is 10, the lowest should be no less than, say 6. (This is a rough guideline only, YMMV.)

 

However, there are ways around this - Area Effect attacks (or Explosions) are great for hitting that hard-to-hit Artful Dodger. Or you can at least make him waste his phases Diving for Cover. Then again there's also Mental Powers which target ECV (MCV).

 

If you want to change the dice rolls, I'd recommend something I've been toying with for a long time - partially because of the exact problem you mention: use "bigger" dice. I recommend 3d12. It preserves the exact same shaped bell curve, only bigger and more granular. The base attack roll then becomes 20- instead of 11-. A Familiarity roll then becomes 15- instead of 8-, and a 14- roll becomes a 25- roll, for example. This way the chances of hitting change by smaller steps. Instead of jumping from 50% at 10- to 62.5% at 11-, you go from 50% at 19- to 56.3% at 20-.

 

Unless I am misunderstanding something your 3d12 system does Far more to distort combat than switching to 2D10 does. A difference of say 4 with 3d6 is 16.2%, with 2d10 it is 21% while using 3d12 it becomes 31.7% chance of hitting. Now a difference of 8 with 3d6 is .46% with 2d10 it is 3% while 3d12 is 12.7%. You also change the chance of a "critical" to roughly 1 in 2000. This increased die size without corresponding changes to the calculation of OCV/DCV and combat modifies does far more to distort the likelihood of success or failure in combat far more than using 2d10. Though the shape of your bell curve won't change you are decreasing the relative size of your sampling due to the structure of combat modifiers. By using 2d10 it is purposefully meant to distort the bell curve, but only slightly making rolling those threes and fours a little easier while making those 14s and 15s less of a gimme.

 

My intent is that using 2d10 has a minimal change on combat for realitively balanced characters(10- on 3d6 is 50% and 45% with 2d10) while making it easier on those less agile characters without imposing harsh limitations on characters OCV and DCV values giving more pc freedom of design or changing the calculated OCV/DCV of NPCs.

[zagman]

Re: Question reguarding To Hit probability

 

I just limit the CVs in a game to a tighter range. Only on rare occasions (Drama!) should CVs move too far from each other.

 

8-12 is a good range for Supers I've found.

Or put another way - a Four Point Spread can make the crack shot feel awesome, while still not being a gimme.

 

You are suggesting imposing limitations on the pcs while I suggest something that softens the system a little for the extremes. A four point crack shot on 3d6 is 16.2% to 21% on 2d10, still just about the same feeling.

 

2d10 also makes those skill check of say a 16(98.1%) a little assured with 2d10 90% giving characters more incentive to spend a couple of extra skill points without changing the chances of success for the 8-14 range too much.

[zagman]

Re: Question reguarding To Hit probability

 

Oh oh' date=' he said realism. If you want the 17 dex guy to be realistic give him 3 or 4 dcv and the 4 or 5 ocv cop can still set/brace and hit him with his 9mm.[/quote']

 

I say realism and playability. I still want to be able to use the default OCV and DCV values generated by their Dex without arbitrarily changing them for realism when a simple change of dice alleviates the problem. Setting and Bracing is fine except for our spd 2 cop it is going to take him an entire turn to do, 1/2phase to move to suitable location, 1/2phase to brace, 1 phase to set. That just seems like a lot to do to give you a reasonable chance of hitting a guy 20meters away.

[bigbywolfe]

Re: Question reguarding To Hit probability

 

I say realism and playability. I still want to be able to use the default OCV and DCV values generated by their Dex without arbitrarily changing them for realism when a simple change of dice alleviates the problem. Setting and Bracing is fine except for our spd 2 cop it is going to take him an entire turn to do' date=' 1/2phase to move to suitable location, 1/2phase to brace, 1 phase to set. That just seems like a lot to do to give you a reasonable chance of hitting a guy 20meters away.[/quote']

Um, yeah. Ever looked up the statistics on how many shots fired, even by trained police, actually hit? It's surprisingly few.

As far as your cop hitting your thief? That's one hell of a quick thief. Nothing wrong with that, it’s just a fact. The cop’s probably going to miss. There's nothing wrong with that either. The thief was just better than the cop, which is what those values indicate .

[Alibear]

Re: Question reguarding To Hit probability

 

I say realism and playability.

 

Not to nitpick, okay I'm gonna' nitpick so sue me - you actually said and / or.

 

 

Sorry, I'm already thinking in SIX mode where all characters have 3ocv/dcv as default - Dex doesn't have anything to do with it.

[Hierax]

Re: Question reguarding To Hit probability

 

2d10 offers a very nice middle-ground between 3d6 and d20 probabilities. It has a slightly greater range of values that 3d6 and a curve that's less steep which makes for better granularity. With a bit of effort it should work great for the HERO System, particularly non-super-heroic games that gain more from the greater differentiation.

 

Many people are happy using 3d6 but if you're not I say go for it! Sure, some may consider it an apocalyptic blasphemy playing HERO with anything but d6s, but if the effort is worth the effect to you, why not do it for your own game?

[torchwolf]

Re: Question reguarding To Hit probability

 

Just one note:

11- on 3d6 has a 62.5% chance of success.

11- on 2d10 has a 55% chance of success.

 

While this doesn't seem much statistically, it _does_ have an impact on many Skill Rolls, To-Hit Rolls, etc. I've thought about 2d10 and other variations as well, but that is one of the reasons I decided against changing it, because the bell curve alters slightly at the very base point used by many of the game system's Rolls.

 

Now, I'm not a mathematician, but there are some impressive studies of alternative rolls and statistical distribution under the 6e discussion threads and elsewhere.

[Crypt]

Re: Question reguarding To Hit probability

 

My main questions are:

What do you guys think of using a 2d10 TH system?

Is there anything in the game that this breaks?

 

IMHO you may easily use this kind of roll without breaking the game, it's close enought to the original one and may fit to a more epic/random* feeling.

 

* call it as you please.

 

Some genres may even need far more explosive rolling method so seeing the very serious 3D6-closed-low roll method as sacred may be a real hindrance.

[prestidigitator]

Re: Question reguarding To Hit probability

 

One nice thing about the 3d6 curve is that even things that seem impossible normally can suddenly become very achievable if you scrimp enough with maneuvers, bonuses, skill levels, etc. (like the brace/set example). I rather like that myself. Inspires creativity and hope.

[PhilFleischmann]

Re: Question reguarding To Hit probability

 

Unless I am misunderstanding something your 3d12 system does Far more to distort combat than switching to 2D10 does. A difference of say 4 with 3d6 is 16.2%' date=' with 2d10 it is 21% while using 3d12 it becomes 31.7% chance of hitting. Now a difference of 8 with 3d6 is .46% with 2d10 it is 3% while 3d12 is 12.7%.[/quote']

I thought that's what you wanted: the guy with the lower CV has some reasonable chance of hitting the guy with the higher CV, and the guy with the higher CV isn't practically guaranteed to hit the guy with the lower CV. If 3d12 is too much of a change in the odds, you can use 3d10 (base to-hit number is 17-), or 3d8 (base to-hit number is 14-). These also preserve the exact same shaped bell curve, only "bigger" - somewhat greater granularity. If you wanted to go even further (which you apparently don't, and neither do I), you could potentially use 3d20, or even 3d30 for a tremendous amount of granularity, but at that point, differences in CV would become far less significant.

 

You also change the chance of a "critical" to roughly 1 in 2000.

That depends on how you determine a "critical." There are no "criticals" in the default rules. But if you want to use a house rule involving critical successes (or failures), you can. Many GMs do. But they don't have to be "Only on a 3". Sometimes we use "make the roll by half" (which really doesn't change the relative odds very much between 3d6 and 3d12 (or 3dAnything). Sometimes people use "make the roll by 5 or more" - for 3d12, this could/should be changed to "make the roll by 8, 9, or 10 or more". Or you can just keep a flat chance of critical by making it "3-4" or "3-5" is a critical.

[zagman]

Re: Question reguarding To Hit probability

 

Thanks for the responses and discussion guys. With the changes that that 6th ed has made it take part of what I was talking about out of the equation by just setting a DCV OCV range.

 

To PhilFleichmann: I understand what you are saying about preserving the bell curve and of all the options you present 3d8 is the best one, though it still causes a large distortion to the probabilities involved in combat. Same idea, two ways of going about it. I tweaked the curve while you just made it bigger.

 

Thanks again.

[Legendsmiths]

Re: Question reguarding To Hit probability

 

I think one of the strongest things I enjoy about 3d6 is that the standard dev is 3, so each 3 point step is a tangible benchmark. The difference between novice and pro, pro and expert, expert and master.

 

This makes it very easy to run the game, set challenges, etc, and the bell curve of 3d6 ensures a consistency of performance that is less of a wild swing.

 

I have played Hero with 2d10, d20, 3d6 roll high, and others, and I have found that 3d6 is just smooth. I haven't had the situation where X-number of mods has pushed a roll too far in either direction that I disagreed with the assessment.

 

Just my .02.