[RPG] How to calculate the attack bonus


My stats are: Str 18, Dex 14, Con 13, Int 13, Wis 11, Cha 6.

Main Hand Weapon, Frost Bastard Sword
Off Hand Weapon, Flaming Bastard Sword

I am playing a Human, Fighter 7. I need to work out what my CMB/CMD is, also and my attack bonus. Thanks in advance!

Edit: My feats are:

  1. Two Weapon Fighting
  2. Weapon Focus
  3. Exotic Weapon Proficiency
  4. Two Weapon Defence
  5. Double Slice
  6. Vital Strike

I can have 1 more feat because I'm level 7.

Bonus question – What 1-handed weapons should I be using?

Best Answer

Attack Routine

Dual-wielding two bastard swords with Two-Weapon Fighting and Exotic Weapon Proficiency (Bastard Swords) causes you to take a −4 penalty for wielding two one-handed weapons. If you were to wield a one-handed weapon in one hand and a light weapon in the other, you’d have only a −2 penalty.

In addition to these penalties, you have BAB +7/+2 (that is, two attacks, one at +7 and the other at +2), and a +4 Strength modifier. As a Fighter, you have Weapon Training, which is a +1 to attack and damage as long as you use weapons from the chosen group (which is another problem because you have to pick between Heavy Blades and Light Blades).

So as it currently stands (with the −4 penalty), your attack routine is this:

Dual-wielding Bastard Swords, Heavy Blade Weapon Training

Bastard Sword +8, 1d10+5 (10.5)

other Bastard Sword +8, 1d10+3 (8.5)

Bastard Sword +3, 1d10+5 (10.5)

If you had a bastard sword and a short sword, you’d instead have a −2 penalty, like so, but you’ll only get Heavy Blade Weapon Training on the Bastard Sword attacks

Bastard Sword and Short Sword, Heavy Blade Weapon Training

Bastard Sword +10, 1d10+5 (10.5)

Short Sword +9, 1d6+2 (5.5)

Bastard Sword +5, 1d10+5 (10.5)

You lose an average of 2 damage on the second attack, but you are far more likely to hit with all three attacks.

If you swapped the Bastard Sword for a Longsword, saving yourself a feat, you would have

Longsword and Short Sword (+1 feat), Heavy Blade Weapon Training

Longsword +10, 1d8+5 (10.5)

Short Sword +9, 1d6+2 (5.5)

Longsword +5, 1d8+5 (10.5)

On average, you lose 1 damage from each of your first and third attacks (2 damage less total), but you have another feat which may be able to give you more damage than that. A really simple example is to switch to purely Short Swords, and take Weapon Focus and Weapon Specialization with them. This also allows the Light Blade Weapon Training to get the bonuses on all of the attacks.

Dual-wielding Short Swords, Weapon Focus and Weapon Specialization (−1 feat), Light Blade Weapon Training

Short Sword A +11, 1d6+7 (10.5)

Short Sword B +11, 1d6+5 (8.5)

Short Sword A +6, 1d6+7 (10.5)

Note that this version has the highest attack bonuses and the same damage potential as the two bastard swords. Weapon Focus and Weapon Specialization are not exactly high-power feats, but they’re better here than Exotic Weapon Proficiency in the Bastard Sword. (to be fair, I used two feats to do it, but Weapon Focus in Bastard Swords doesn’t really help much since either you’re taking huge penalties for using two or you’re only getting the bonus on two out of three attacks)

Alternatively, you could consider Improved Two-Weapon Fighting, either with Exotic Weapon Proficiency in Bastard Swords:

Bastard Sword and Short Sword, Improved Two-Weapon Fighting (−1 feat), Heavy Blade Weapon Training

Bastard Sword +10, 1d10+5 (10.5)

Short Sword +9, 1d6+2 (5.5)

Bastard Sword +5, 1d10+5 (10.5)

Short Sword +4, 1d6+2 (5.5)

Or with Weapon Focus (Short Sword)

Dual-wielding Short Swords, Improved Two-Weapon Fighting and Weapon Focus, Light Blade Weapon Training

Short Sword A +11, 1d6+5 (8.5)

Short Sword B +11, 1d6+3 (6.5)

Short Sword A +6, 1d6+5 (8.5)

Short Sword B +6, 1d6+3 (6.5)

Note that in the second case, you average 2 damage less on half your attacks, but have +1 on all attacks.

There are still better things you could probably do, these are just some simple, Core feat choices that you should consider without changing your existing feats too much.

Combat Maneuver Bonus/Defense

CMB = BAB + Str + size_bonus + misc

You don’t have a size bonus if you’re Medium (like Humans generally are), so ignore that. The Fighter’s Weapon Training also gives you a +1 as long as you’re using the right weapon, so +1 for that. Your BAB is +7 and your Strength modifier is +2, so your CMB is +10.

CMD = BAB + Str + Dex + size_bonus + misc

Again, size and misc don’t come into play. Weapon Training only helps against Disarm or Sunder, so I won’t include in the general number. So you have +7 + 2 + 2 = +11.