I am quite new to playing DND and I'm struggling to understand how a bat has +0 to attack. I'm clearly missing something, but as per my calculations:
A bat has a strength of 2 (-4 Modifier).
This is countered by a +2 of proficiency.
Looking at the bite attack (emphasis mine):
Bite. Melee Weapon Attack: +0 to hit, reach 5 ft., one creature. Hit: (1d1) piercing damage.
How is this calculated to +0? Should this not be -2?
Best Answer
I don't think there is a formula that will give us that +0.
The bat is a very weak creature, with a CR 0. Most likely, the D&D designers just didn't want him to have a negative attack modifier, so they set it at 0, despite having -4 STR and +2 DEX.
It was a balance decision. The bat also does 1-damage with that attack, which is not derived from any formula. An unarmed strike is usually 1+STR, and a natural attack 1d4+STR, so both would deal non-positive damage.
From the DMG, on Creating Monsters (credit to Sdjz):
Also, AFAIK, there aren't monsters with negative attack modifiers, are there?