Question about the maths behind attack roll and defense rolls

SuedodeuS · 04-13-2010, 08:13 PM

The concept is that the attack roll is answering the yes/no question of "Did you swing well enough to connect?" while the defense roll is answering the yes/no question of "Did you get out of the way/interpose an object in time?" The reason Quick Contest mechanics aren't used is because of choice. I'm not particularly good at combat - I might have Karate Sport at DX. Against someone who's decent, I can throw attacks that should connect all day, only to have them Parried or Dodged. I can increase my chances of scoring a hit by getting tricky - a quick fake-out before an attack, a particularly rapid attack, trying to hit that little opening I see, etc. In all cases wherein I do this, however, there's a trade-off - I have a higher chance (and I've actually noticed this) of missing outright, without need for my opponent to do anything to avoid the hit. This is what GURPS calls a Deceptive Attack*, which imposes -2 to hit for -1 to the enemy's defense. From the other side, the situation is fairly comparable - I can Parry or Dodge (retreating in both cases) their normal attacks fairly well, and they will frequently do a fake-out or quick attack in order to connect. The important thing here is that there is a risk, and the fighter must choose to engage in this risk in order to benefit from it. When you make an attack, you (in general) make the attack you were intending - you don't mess up and suddenly make it better.

That said, including Quick Contest like mechanics won't break the game, although they will result in more hits. The element of risk on the part of the attacker is lessened, as he needn't sacrifice his chances of hitting to decrease the chances of a successful defense. Do note, however, that Parry is based on half one's skill level - so it would be appropriate to half the attacker's Margin of Success to determine the penalty. If you don't like doing this, you could adopt the rules from T-bone's FEND (Fully ENabled Defenses) system, where Parry is Skill, rather than (Skill/2)+3, Dodge is Basic Move*2 (instead of Basic Move+3), defenses take a general -4 penalty, and penalties from Feints are doubled. In that, Deceptive Attacks trade off on a 1-for-1 basis - using Quick Contest mechanics, this simply means you are automatically going as deceptive as possible and still landing a hit.

*At my skill level, I'm probably doing something more akin to Telegraphic Attack normally, and then simply being less telegraphed when I do what I'm calling a Deceptive Attack. The math works out the same either way, however.

04-13-2010, 08:13 PM	#9
SuedodeuS Join Date: Sep 2008	Re: Question about the maths behind attack roll and defense rolls The concept is that the attack roll is answering the yes/no question of "Did you swing well enough to connect?" while the defense roll is answering the yes/no question of "Did you get out of the way/interpose an object in time?" The reason Quick Contest mechanics aren't used is because of choice. I'm not particularly good at combat - I might have Karate Sport at DX. Against someone who's decent, I can throw attacks that should connect all day, only to have them Parried or Dodged. I can increase my chances of scoring a hit by getting tricky - a quick fake-out before an attack, a particularly rapid attack, trying to hit that little opening I see, etc. In all cases wherein I do this, however, there's a trade-off - I have a higher chance (and I've actually noticed this) of missing outright, without need for my opponent to do anything to avoid the hit. This is what GURPS calls a Deceptive Attack, which imposes -2 to hit for -1 to the enemy's defense. From the other side, the situation is fairly comparable - I can Parry or Dodge (retreating in both cases) their normal attacks fairly well, and they will frequently do a fake-out or quick attack in order to connect. The important thing here is that there is a risk, and the fighter must choose to engage in this risk in order to benefit from it. When you make an attack, you (in general) make the attack you were intending - you don't mess up and suddenly make it better. That said, including Quick Contest like mechanics won't break the game, although they will result in more hits. The element of risk on the part of the attacker is lessened, as he needn't sacrifice his chances of hitting to decrease the chances of a successful defense. Do note, however, that Parry is based on half* one's skill level - so it would be appropriate to half the attacker's Margin of Success to determine the penalty. If you don't like doing this, you could adopt the rules from T-bone's FEND (Fully ENabled Defenses) system, where Parry is Skill, rather than (Skill/2)+3, Dodge is Basic Move2 (instead of Basic Move+3), defenses take a general -4 penalty, and penalties from Feints are doubled. In that, Deceptive Attacks trade off on a 1-for-1 basis - using Quick Contest mechanics, this simply means you are automatically going as deceptive as possible and still landing a hit. At my skill level, I'm probably doing something more akin to Telegraphic Attack normally, and then simply being less telegraphed when I do what I'm calling a Deceptive Attack. The math works out the same either way, however. __________________ Quos deus vult perdere, prius dementat. Latin: Those whom a god wishes to destroy, he first drives mad.