Active defenses as modifiers

[benz72]

Maybe making the calculation is quicker, but it isn't obvious to me on the face of it. How long does it take to recalculate the modifier vs. how long to make the additional roll?
If speed is the issue, replacing 2 second task A with 2+ second task B might not have the desired effect.
If it is indeed quicker, how much time did you save?

[Varyon]

Originally Posted by benz72

Maybe making the calculation is quicker, but it isn't obvious to me on the face of it. How long does it take to recalculate the modifier vs. how long to make the additional roll?
If speed is the issue, replacing 2 second task A with 2+ second task B might not have the desired effect.
If it is indeed quicker, how much time did you save?

I'd imagine you'd just write what your Defense Modifier is on your sheet ahead of time, then when someone attacks you just see if their MoS was enough to soak the penalty. So if you have Block 15, Parry 12, and Dodge 9, you just note that you impose a -5 to hit with a Block, -4 with a Parry, and -3 with a Dodge.

But the proposed system gives radically different hit probabilities compared to RAW. Assuming equal skill and further assuming no bonuses (Combat Reflexes, shields, etc), you're typically looking at around a 45% chance of successfully hitting the foe (succeed on attack, fail on defense) if you're using Deceptive Attack (or even Telegraphic Attack at low skill) to get your skill to around 13-14, which generally gives the highest overall hit probability. With the proposed system, you need to look at multiples of 6 (when the defense bonus changes). At skill 12, that's Parry 9 and thus -3 to hit; that gives a 37.5% chance of actually hitting, which may be close enough to 45% to work alright. But at skill 18, Parry 12 gives only a -4 to attack; that gives a 91% chance of actually hitting. At skill 24, Parry 15 gives a -5; you're at the cap of ~98% chance of actually hitting, and any higher skill is above that. Looking at the in-betweens, skill 13 gives an overall hit probability of 50% (close enough to 45%), 14 is 62.5% (too high from here on), 15 is 74%, 16 is 84%, 17 and 18 are each 91%, 19 is 95%, and 20+ are all 98%.

EDIT: An alternative option that may come closer to the RAW distribution would be to subtract your skill (or 2xBasic Speed for Dodge) from 10 to determine the penalty (which will mean a bonus against those with skill below 10, but that kinda represents using Telegraphic Attack against those). For defense modifiers, like from Shields, Enhanced Defenses, etc, you'd double them and apply as a further penalty (which also means you could have higher resolution - instead of DB 1, DB 2, and DB 3 shields, you could have -1, -2, -3, -4, -5, and -6 shields; meanwhile Combat Reflexes would probably only impose a -1 and you could have half-levels of Enhanced Defense available that only give -1 each). This matches pretty well for equal skill (50% chance instead of 45%), but will deviate the further apart the characters' effective skills are.

[Tinman]

my big problem with this is: as a PC it takes away all agency I have as a player.
I should be able to adjust my defenses, use retreat or FP as I see fit & then rely on MY luck/roll to determine if I get hurt or not. I don't like that it's all on some other guy's roll.

Also, does you modifier let me choose to retreat or fp defense?

[ravenfish]

Originally Posted by Tinman

Also, does you modifier let me choose to retreat or fp defense?

I don't see why it wouldn't- you declare them when the opponent attempts his attack roll rather than after it succeeds, and they penalize his attack roll rather than benefiting your defense roll.

In principle, I see no reason why such a system could not be made to work, but, for me personally, getting to roll for a parry or dodge (rather than having my skill at parrying or dodging abstractly reduce the opponent's chance to hit) is part of the attraction of GURPS, and I doubt I'm the only one with such feelings.

[Fred Brackin]

Originally Posted by Tinman

my big problem with this is: as a PC it takes away all agency I have as a player.
I should be able to adjust my defenses, use retreat or FP as I see fit & then rely on MY luck/roll to determine if I get hurt or not. I don't like that it's all on some other guy's roll.

I came into the hobby in the late 70s with a _lot_ of combat in Chivalry & Sorcery 1e which worked a lot like this. It was nice when you were the more skilled fighter that it was more difficult to be parried or dodged.

I found Gurps with its' "flat" defenses to be somewhat annoying. Some of this may have been before I appreciated the ability of crits on attacks to be always successful.

Runequest 2 may have had some of this "A successful defense always beats a successful attack" problem.

[Rupert]

Originally Posted by Fred Brackin

I came into the hobby in the late 70s with a _lot_ of combat in Chivalry & Sorcery 1e which worked a lot like this. It was nice when you were the more skilled fighter that it was more difficult to be parried or dodged.

I found Gurps with its' "flat" defenses to be somewhat annoying. Some of this may have been before I appreciated the ability of crits on attacks to be always successful.

Runequest 2 may have had some of this "A successful defense always beats a successful attack" problem.

In Runequest 2 at least a successful attack could damage the parrying weapon or possibly smash through a shield.

Rolemaster also works like the OP is looking at. One of the potential issues with doing this in GURPS is that it makes anything that reduces your hit chance very bad. It also makes deceptive attacks worse than useless, but this might no be of concern if skills aren't expected to get over twenty or so.

By the way, this also applies to doing quick contests - anything that might reduce your margin of success has to return huge dividends, so wise players will make very few targeted attacks, etc.

[Anthony]

The main incentive for doing something like this is streamlining: GURPS combat with can turn into quite a slog of failed attacks (this is particularly common when using shields) so cutting down on the number of rolls will cut speed things up. There's other ways of accomplishing the same thing, though (changing combat to a quick contest, for example).

[benz72]

I've seen the slogfest argument before, and taken it seriously, but every time I look into it more deeply I come across a failure to utilize terrain and tactics to change the dynamics of the fight. I get that the default attack-defend-damage loop can get boring and crit fishing is dull, but suggest that we generally do have good options to make fights interesting without actually changing the rules.

[Anthony]

Originally Posted by benz72

I've seen the slogfest argument before, and taken it seriously, but every time I look into it more deeply I come across a failure to utilize terrain and tactics to change the dynamics of the fight.

Problem is the enemy will also try to utilize terrain and tactics to change the dynamics in their favor, and that usually cancels out.

[Varyon]

Originally Posted by benz72

I've seen the slogfest argument before, and taken it seriously, but every time I look into it more deeply I come across a failure to utilize terrain and tactics to change the dynamics of the fight. I get that the default attack-defend-damage loop can get boring and crit fishing is dull, but suggest that we generally do have good options to make fights interesting without actually changing the rules.

Again, with equally-skilled combatants, you're looking at around a 45% chance of a hit, which isn't a slogfest - it's close to one out of every 2 attacks hitting. That changes as the target's defense goes up, of course - against a foe with a +1 to defenses, you're looking at around a 34% chance (one-in-three), with +2 it's around a 24% chance (one-in-four), with +3 it's around a 15% chance (one-in-seven), and with +4 it's around an 8% chance (one-in-twelve). But then a slogfest is kind of the expectation of equally-skilled combatants wielding large shields anyway - the whole point of shields is to prevent you from getting hurt! With combatants who aren't equally skilled, the more-skilled one will have an easier time than the above values - skill 14 vs skill 12 gives around a 57% chance of a hit, 14 vs 10 is around 67%, 14 vs 8 is around 76%, and 14 vs 6 is around 83%. Needing to target somewhere other than the Torso also serves to drop the attacker's effective skill, which will make it take longer to score a hit - but then trying to hit someone in the head should take longer to score a hit than just going after the Torso.