This tiefling warlock at level 5 from WotC's site has a dagger attack I can't figure out:
Dagger. Melee Weapon Attack:
+6 to hit, reach 5 ft. or range 20/60 ft., one target.
Hit: 1d4 + 2 piercing damage.
First, I can't figure out why the dagger does 1d4 + 2 piercing damage. Looking at page 149 of the Player's Handbook, the dagger only shows that it is 1d4 piercing, nothing more, so I really don't know where the +2 piercing damage comes from.
Second, nowhere in the weapon's listing says how to figure the attack bonus. Where in the Player's Handbook does that +5 to hit come from?
I've seen a question here which states that for ranged weapons attacks the attack bonus is calculated as Dexterity modifier + proficiency bonus, whereas melee attacks it is strength + proficiency bonus, but on the 5th-level Tiefling Warlock's sheet you can see his stats don't reflect that:
Str: 8 (-1)
Dex: 15 (+2)
Con: 14 (+2)
Int: 13 (+1)
Wis: 10 (0)
Cha: 18 (+4)
With those stats the melee attack bonus for a dagger should be −1 (Strength modifier) + 3 (proficiency bonus) = +2.
But it isn't — it is +6. Why?
Best Answer
Daggers are melee weapons that have the finesse property. The finesse property allows an attacker to use their dexterity modifier for their attack bonus and damage bonus, in place of the strength modifier.
In this case, the tiefling has a +3 proficiency bonus and a +2 dex modifier, so the attack bonus should be +5 with a finesse weapon, unless there is something missing from the sheet that explains the extra +1 to bring it to +6 such as the dagger being a magic weapon or something. That doesn't appear to be the case here because the equipment for the character is listed on the sheet but something is not adding up correctly, or else I'm missing something on the sheet completely.
As for the piercing damage question, piercing is the type of damage the dagger does. The table in the equipment chapter that details the weapons tells the reader what damage die a weapon uses and also the damage type for the weapon. A dagger does 1d4 damage, and the damage type is piercing. The damage bonus is calculated by adding the attack modifier (in this case dexterity because the weapon has the finesse property) plus any other modifiers to the damage (in this case, none), giving a total of 1d4 + 2.
I'm not certain why the sheet is showing the attack bonus as +6 to hit. All of these sheets seem to have an extra 1 that I can't figure out the source of. If someone finds it, please comment because it's really bothering me and I don't know if I'm just missing something plainly obvious.
I'm leaning towards the calculations on all of these sheets being wrong and chalking it up to an error on the first sheet not being checked and being carried over to every other sheet after. I can see no reason why the bonus is +1 higher than it should be, especially since the spell attack modifier is calculated correctly using the warlock's charisma bonus + proficiency modifier.