Combat attack bonus/AC question [Archive] - Wizards Community

Combat attack bonus/AC question [Archive] - Wizards Community

Post/Author/DateTime Post
Elrendur
12-23-04, 07:20 PM I’ll be the first to admit I’m a Grognard. I haven’t played or DM’d since 2nd Ed, but that is about to change shortly as I start running a 3.5 game. And I have a newbie-ish question (probably the first of many).

After reading through the rules, I have a tiny bit of confusion over the size modifier to the combat roll and AC. When the modifier is applied to the die roll, is it the modifier of the attacking creature or the creature being attacked that is added? I have the same question in regards to AC.

In other words, is it true that a human attacking a halflings would roll a d20, add his/her base attack bonus, strength modifier, and the size modifier of 0 because a human is Medium sized. Said attack roll would go against the halfling’s AC of 10 + armor + shield + dexterity modifier + the size modifier of +1 due to the halfling’s Small size...

Is that the correct interpretation? That is the simplest way I find of interpreting said rules, but I like to make things much more complicated than necessary most of the time, hence my confusion.

Thanks!
masterofmayhem
12-23-04, 07:35 PM That's right. The simplest way to think of it is to act like you're comparing the small (or large, huge, whatever) creature to a medium one. So a small creature is 1 size category smaller than a medium one so gets +1 to AC and attack, a huger creature is 2 size categories larger than a medium creature, so has -2 to AC and attack.

While, at first glance, it seems like a Large creature would then have a harder then normal time attacking a medium creature, this is not true. Two large creatures are the same size, so hould have no modifers to AC and attack. This is already figured into their stats with both -1 AC and -1 to attack, so it evens out, making them equal.

Hope that helps. :)
Zherog
12-23-04, 10:36 PM Your interpretation is correct, Elrendur. Some other things to note (to extend it further):

When the halfling attacks the human, the halfling gains a +1 to hit, but the human doesn't adjust AC at all.

Going one step further... let's have the halfling attack an ogre - a large creature. Well, the halfing still only gets a +1 to the attack role. This bonus doesn't change. However, the ogre (as a large creature) also gets a -1 to AC. In effect, the halfling has a +2 to hit the ogre, though it's reflected as a +1 to hit and a -1 to the ogre's AC.

What that all comes down to is that the size mods are constants, and don't ever get adjusted. As long as you apply the correct bonuses, things will work out right (mathematically) in the end.

Oh - and welcome to the boards. :)
Nom
12-26-04, 09:15 PM To finish Zherog's example...

When the human attacks the halfling, the human has no modifier to his attack, but the halfling has a +1 size bonus to AC. The net effect is +1 in the halfling's favour, just as when the halfling attacked the human.

When the ogre attacks the halfling, the ogre has a -1 size penalty to his attack roll and the halfling gains a +1 size bonus to AC. The net effect is +2 in the halfling's favour, just as when the halfling attacked the human.

The net modifier is the same no matter which way you go, but the modifiers are applied constantly for non-medium creatures.

One quirk is that above Huge and below Tiny the modifiers get bigger, rather than +/-1 per size step. The game is calibrated around Medium creatures.

Post/Author/DateTime	Post
Elrendur 12-23-04, 07:20 PM	I’ll be the first to admit I’m a Grognard. I haven’t played or DM’d since 2nd Ed, but that is about to change shortly as I start running a 3.5 game. And I have a newbie-ish question (probably the first of many). After reading through the rules, I have a tiny bit of confusion over the size modifier to the combat roll and AC. When the modifier is applied to the die roll, is it the modifier of the attacking creature or the creature being attacked that is added? I have the same question in regards to AC. In other words, is it true that a human attacking a halflings would roll a d20, add his/her base attack bonus, strength modifier, and the size modifier of 0 because a human is Medium sized. Said attack roll would go against the halfling’s AC of 10 + armor + shield + dexterity modifier + the size modifier of +1 due to the halfling’s Small size... Is that the correct interpretation? That is the simplest way I find of interpreting said rules, but I like to make things much more complicated than necessary most of the time, hence my confusion. Thanks!
masterofmayhem 12-23-04, 07:35 PM	That's right. The simplest way to think of it is to act like you're comparing the small (or large, huge, whatever) creature to a medium one. So a small creature is 1 size category smaller than a medium one so gets +1 to AC and attack, a huger creature is 2 size categories larger than a medium creature, so has -2 to AC and attack. While, at first glance, it seems like a Large creature would then have a harder then normal time attacking a medium creature, this is not true. Two large creatures are the same size, so hould have no modifers to AC and attack. This is already figured into their stats with both -1 AC and -1 to attack, so it evens out, making them equal. Hope that helps. :)
Zherog 12-23-04, 10:36 PM	Your interpretation is correct, Elrendur. Some other things to note (to extend it further): When the halfling attacks the human, the halfling gains a +1 to hit, but the human doesn't adjust AC at all. Going one step further... let's have the halfling attack an ogre - a large creature. Well, the halfing still only gets a +1 to the attack role. This bonus doesn't change. However, the ogre (as a large creature) also gets a -1 to AC. In effect, the halfling has a +2 to hit the ogre, though it's reflected as a +1 to hit and a -1 to the ogre's AC. What that all comes down to is that the size mods are constants, and don't ever get adjusted. As long as you apply the correct bonuses, things will work out right (mathematically) in the end. Oh - and welcome to the boards. :)
Nom 12-26-04, 09:15 PM	To finish Zherog's example... When the human attacks the halfling, the human has no modifier to his attack, but the halfling has a +1 size bonus to AC. The net effect is +1 in the halfling's favour, just as when the halfling attacked the human. When the ogre attacks the halfling, the ogre has a -1 size penalty to his attack roll and the halfling gains a +1 size bonus to AC. The net effect is +2 in the halfling's favour, just as when the halfling attacked the human. The net modifier is the same no matter which way you go, but the modifiers are applied constantly for non-medium creatures. One quirk is that above Huge and below Tiny the modifiers get bigger, rather than +/-1 per size step. The game is calibrated around Medium creatures.