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Old 04-18-2018, 01:21 PM   #21
weby
 
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Default Re: High defenses in 4th edition

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Originally Posted by Tomsdad View Post
Hang that's not right, a defender's good roll negates an attacker's good roll.
yes. But if a attacker rolls a bad roll, it does not matter what the defender roll is, the result is a 0 bonus. But the opposite is not true.


So 2 examples of attacker roll with 3 corresponding defender rolls.

Attacker rolls a 5: Defender 5: 0 bonus
Attacker rolls a 5: Defender 10: +5 bonus
Attacker rolls a 5: Defender 15: +10 bonus

Attacker rolls a 15: Defender 5: 0 bonus
Attacker rolls a 15: Defender 10: 0 bonus
Attacker rolls a 15: Defender 15: +0 bonus

See the difference?


Quote:
In terms of reducing the chance of successful defence by penalising by 1 yes, but the effect of the DA is different than the Feint because it doesn't have the QS that evens the effect out.
Yes, but at low skills the deceptive attack reduces you chances of actually hitting so that is an effect that actually affects too.

Quote:
And unless you have really high defences most defence scores are grouped closer to the bell curve peak, and generally speaking most attacking scores are higher than them so you tend to get more 'bang for your buck' trading 2 off you attack for 1 of your target's defence.

But yes the closer your target's defence score is to your attack score the less benefit you see from DA's (unless you are over 17 on the attack in which case it's a free penalty even if it's not a big one)
I am at least talking of scenario given by OP, where the skill is 14 and likely defense(with retreat and combat reflexes as likely in one on one) of 13 or 14.

If you change the parameters the thing is of course different.

Quote:
sorry I may have missed that example, but I'm not sure that works, 34% every 2nd round is not the same as 17% each round for two rounds? You're thinking in terms of an abstract average hit per round, but that's not the same.

even leaving aside the effects of multiple chances, you have two chances of critical hit and that chance is likely static for each event.
Yes that is exactly how probabilities work.

The 1.85% probability to crit at skill 14/attack is calculated in as 1.85%/round for the one attack/round person and half that for the other in the final hit chance.

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Either-way in terms of comparing it to two attacks it really depends on how much you increase your chances of getting through with a feint. That depends on where the defence scores are on the bell curve and the chances of net MoS on the feint.
Of course it does, but the scenario and values were given by the OP. If you change the scenario you obviously have to recalculate, but the actual recalculation is done in the same way.

Quote:
That's before we get into questions of what happens if person A hits person B and inflicts a shock penalty after person B feints but before that feint is capitalised on (what you gain in penalising the opponent's defence you might well lose in penalised attacks, and that's leaving aside the other issues of being hit!)
Well, the odds are on the side of the feinter in that he will be the one doing the damaging with the high defenses really making hits without that unlikely.

All the things I have written are in context of the OPs numbers and probabilities. If you change the numbers the calculation changes and actual dice rolls are of course random, but in the long run following the odds is likely a better idea than not following them.. :)
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Old 04-18-2018, 02:10 PM   #22
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Default Re: High defenses in 4th edition

At equal skill, we expect the attacker to win the contest 45.4% of the time, with an average margin of success of 3.367. If the attacker knows he won, he spent a total of 3.2 attacks.

At equal skill, ideal deceptive attack is easily calculated:
Defense=Skill/2+1: DA to 14, defender parry 8. Hit chance 68%.
Defense=Skill/2+2: DA to 14, defender parry 9. Hit chance 57%.
Defense=Skill/2+3: DA to 12, defender parry 9. Hit chance 47%.
Defense=Skill/2+4: DA to 12, defender parry 10. Hit chance 38%.
Defense=Skill/2+5: DA to 12, defender parry 11. Hit chance 29%.
Defense=Skill/2+6: DA to 12, defender parry 12. Hit chance 21%.
Defense=Skill/2+7: DA to 10, defender parry 12. Hit chance 14%.
Defense=Skill/2+8: if skill 16+, try to roll crits. Hit chance 11%

So, for the feint to be worthwhile, figure it's -3 defender parry but need to multiply hit chance by 3. Checking the above:
29%/11% = 2.64
38%/14% = 2.71
47%/21% = 2.24
57%/29% = 1.97
68%/38% = 1.79

Conclusion: a feint against an equal skill opponent is not worthwhile unless unusual circumstances are in effect.
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Old 04-18-2018, 05:40 PM   #23
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Default Re: High defenses in 4th edition

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Originally Posted by weby View Post
yes. But if a attacker rolls a bad roll, it does not matter what the defender roll is, the result is a 0 bonus. But the opposite is not true.

Yes but that doesn't effect the fact that the margin of victory is what defines the end result (it just ends the sliding scale of margin of victory at net zero success = no effect, anything past that is irrelevant and you can't get any more no effect, than no effect.


Quote:
Originally Posted by weby View Post
So 2 examples of attacker roll with 3 corresponding defender rolls.

Attacker rolls a 5: Defender 5: 0 bonus
Attacker rolls a 5: Defender 10: +5 bonus
Attacker rolls a 5: Defender 15: +10 bonus

Attacker rolls a 15: Defender 5: 0 bonus
Attacker rolls a 15: Defender 10: 0 bonus
Attacker rolls a 15: Defender 15: +0 bonus

See the difference?
Yes but the attacker is just as likely to roll 5, 10 and 15 as the defender, so you comparing the wrong things, or rather you are comparing pairs of results that are not equally likely. And we are interested in the over net outcome chances or the distribution of results.

a like for like comparison as in comparing an equally likely distribution of results is:

Attacker rolls 1 defender rolls 1 = 0 net
Attacker rolls 2 defender rolls 2 = 0 net
....
Attacker rolls 10 defender rolls 10 = 0 net

and so, in each pair each side is as likely as the other.


The point being if the skill is equal each has the same distribution of MoS as the other. As the defenders MoS negates the attackers on a one for one basis, and is as likely to occur as the attackers there is no net gain on average. Again you have to look at the overall distribution of margin of victory.


Yes the attacker could get a margin of victory of 10 MoS, but it's just as likely that the defender will. Same is true for 5 margin of victory or 2 or 0 and so on. Now as you say it doesn't matter how much the defender wins by, but that's not the point because that's not what we're looking at here. For there to be an advantage for the attacker ie. the odds to be in their favour instead of 50/50* there has to be more chance of them getting more MoS than the defender. But that isn't the case as they have the same distribution of chances to get the same results as each other, because they have the same skill and thus the same chances of getting the same MoS as each other.


Put it simply I have Skill 14 and you have skill 14, we each roll 3d6, who do you bet on to win?


Another way to look at it, lets say GURPS works on flipping coins, and a QC is decided by the attacker and defender flipping coins. each head that comes up is a success each tails is not. If both are of equal skill we flip the same number of coins.

So the point is we each have the same chance of getting successes as each other just like in a GURPS QC counting MoS against the same skill level.

Now yes it is possible for one to flip more heads than the other even if we flip the same number of coins (one flipped coins better), just as it's possible for a QC against equal skills to have one come up with more MoS than anther (one rolled lower).

Now the more coins we both flip the greater the margin in victory can potentially be. If we both flip 2 coins the greatest margin of victory possible is 2 , if we both flip 10 it's 10. Just as is the case if we ere doing GURPS QC against skill 15 each as opposed to 5 each.

But neither side has an advantage. (and of course any net win by the defender is a total win, and in fact so is a draw)



*or in fact 45/55 I think as ties go to the defender

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Originally Posted by weby View Post
Yes, but at low skills the deceptive attack reduces you chances of actually hitting so that is an effect that actually affects too.
True, but that wasn't really my point, I was more pointing out the difference's between DA and Feint.



Quote:
Originally Posted by weby View Post
I am at least talking of scenario given by OP, where the skill is 14 and likely defense(with retreat and combat reflexes as likely in one on one) of 13 or 14.

If you change the parameters the thing is of course different.
I agree, I pointed that out.

Quote:
Originally Posted by weby View Post
Yes that is exactly how probabilities work.

You think having two chances at 17% is the same as having one chance at 34% (in terms of number of likely successful hits)?

I think you talking about averaging hits over time with one distribution, rather than comparing probabilities of two different ones over the same time.


Quote:
Originally Posted by weby View Post
The 1.85% probability to crit at skill 14/attack is calculated in as 1.85%/round for the one attack/round person and half that for the other in the final hit chance.
Yes so not equal chances of getting a crit, but rather a greater chance of the two rolls?

(of course if the single better change of general success also tips over the Critical range that changes)


Quote:
Originally Posted by weby View Post
Of course it does, but the scenario and values were given by the OP. If you change the scenario you obviously have to recalculate, but the actual recalculation is done in the same way.
Right but your graph was talking about likely MoS of success a fient QC of equal Skill should expect to get. That didn't bring in the defender's subsequent defence, that what I'm questioning

Quote:
Originally Posted by weby View Post
Well, the odds are on the side of the feinter in that he will be the one doing the damaging with the high defenses really making hits without that unlikely.

All the things I have written are in context of the OPs numbers and probabilities. If you change the numbers the calculation changes and actual dice rolls are of course random, but in the long run following the odds is likely a better idea than not following them.. :)
True, it's just I literally don't like your odds ;-)!


Honestly give it go throw a bunch of equal QC feints see what the end result is over 10 or 20 in terms of how many successfully inflict defence penalties. Ties go to the defender of course, and remember you are halving your attacks by doing that. You have to have pretty tiny chance of getting past you opponents defences for this to be a net positive tactic, especially when you take into account Crit fishing. If they have such a huge defence requiring such a tactic you need a great feint result to see much benefit, and if your skills are equal your chances of getting a great feint are low even if you mange to win the QC (you have to roll well and they have to roll badly).

Last edited by Tomsdad; 04-19-2018 at 03:29 AM.
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Old 04-18-2018, 08:48 PM   #24
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Default Re: High defenses in 4th edition

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Originally Posted by Anthony View Post
Remember, a GURPS turn is a second. Even in the all-out defense case, average hits expected in a 6 second period (D&D turn) is about 0.5.
I always appreciate it when someone reminds us of the nature of the one second turn. It is a significant design model in GURPS with consequences.
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Old 04-18-2018, 08:53 PM   #25
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Default Re: High defenses in 4th edition

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Originally Posted by Kelly Pedersen View Post
With someone just as good as you, you've basically got to wait for lucky breaks (i.e., critical hits) to really succeed.
I think the combat system may work well, but I want to voice an opinion that may be a bit premature.

I'm a bit bothered by the necessity to over rely on critical hits. If two opponents have high attack and defense skills, it seems a bit perverse that the usual success roll mechanics fail to apply as well as the alternate critical hit mechanics as sophisticated as they are. Why should defense skill only matter when its low enough to warrant normal success rolls? (When relying on critical hits, defense ability loses meaning.) In effect, a two-tiered combat mechanic emerges.

I'm not really asking for a solution as much as making an observation. Every system has its idiosyncrasies.

Last edited by Tom H.; 04-18-2018 at 08:56 PM. Reason: Grammar
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Old 04-18-2018, 09:11 PM   #26
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Default Re: High defenses in 4th edition

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Originally Posted by Tom H. View Post
I'm a bit bothered by the necessity to over rely on critical hits.
I wouldn't describe this as a "necessity" by any means. The circumstances I was talking about (equal combat skills, and no opportunities to exploit the environment or tactics against the opponent) are, in my experience, very rare. Usually, there's going to be some way to reduce the opponent's defense. Personally, since I feel that that kind of thing is what makes combats actually interesting, I'm in favor of this result.
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Old 04-18-2018, 09:26 PM   #27
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Default Re: High defenses in 4th edition

Quote:
Originally Posted by Tom H. View Post
I'm a bit bothered by the necessity to over rely on critical hits. If two opponents have high attack and defense skills, it seems a bit perverse that the usual success roll mechanics fail to apply as well as the alternate critical hit mechanics as sophisticated as they are. Why should defense skill only matter when its low enough to warrant normal success rolls? (When relying on critical hits, defense ability loses meaning.) In effect, a two-tiered combat mechanic emerges.
Well, at Attack-12 and Defense-11 (the OP's 14/12 with a -2 Deceptive Attack), hits due to an ordinary hit and a failed defense outnumber critical hits somewhere around 15 to 1. You can make yourself basically immune to normal successful attacks (All-Out Retreating Defensive Grip Quarterstaff Parry), but an almost perfect defense with no attack cannot win a fight. Only last long enough to demonstrate what the word "almost" means.
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Old 04-18-2018, 09:32 PM   #28
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Default Re: High defenses in 4th edition

It is really not uncommon in games I've played to have PCs with active defenses in the 16-20 range before retreat bonuses, and to face enemies with similar defense levels. Deceptive attacks to off-shield flanks, two-or-more on one, rear attacks, magical spells for debuffs, bad footing, feints, close combat attacks (including grapples) - all of these things serve to push down defenses, and while 'one on one, both facing each other' would be interminable, neither PCs nor opponents ever actually do that.
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Old 04-18-2018, 09:38 PM   #29
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Default Re: High defenses in 4th edition

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You can make yourself basically immune to normal successful attacks (All-Out Retreating Defensive Grip Quarterstaff Parry),
And this, right here, is the crux of the issue with the extremely high defenses with middling skill levels. You make it very difficult for the opponent to hit you, but you also make it impossible to hit your opponent. Which means that it is only a matter of time before he hits you enough to kill you. It is not a winning tactic. It is not even a survival tactic unless you are just trying to stall your opponent long enough for something else to happen (which can be a valid tactic in some situations; e.g. to hold the enemies back long enough for the mage to cast his spell, or to let the explosives go off, or for your friend to make it over to you so you can double-team the opponent, or whatever). However, in and of itself, if you are relying on Retreating and - especially - if you are relying on All Out Defending, you are not playing to win the fight.
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Old 04-18-2018, 09:42 PM   #30
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Default Re: High defenses in 4th edition

The important thing to remember: in real life “defense is to offense as 3 is to one”... and it’s true.

However the defender sacrifices the tactical and sometimes strategic initiative.

In GURPS terms, the opponent who all out defends and constantly retreats can’t defend an objective or person, can’t hold an ally’s flank, can’t end the fight except by surrender or fleeing the field and EVENTUALLY an attack will get thru.

That’s pretty close to real life.

...as detailed above, in game terms, there are several ways to reduce the “near perfect” defense.

However, your NEAR perfect defense is giving your opponent a PERFECT defense... you can’t hit them at all... so in the long run, you lose.
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