[RPG] Using ablitity modifers for monsters/creatures

ability-scoresdnd-5e

Looking for some input using ability modifiers for monsters/creatures when using their attack rolls.

The example would be a Level 1 PC vs a Twig Blight. This is assuming there is no advantage vs disadvantage.

Based on MM pg 32, Twig Blight’s attack is melee using its claws. Its Strength is 6 with a -2 modifier. The PHB on pg 176 refers to Strength modifiers, but it’s in the context of PLAYERS, not monsters/creatures. Does the same rule apply for monsters/creatures?

For example,
PC’s AC is 12
Twig Blight rolls a 12 – does it hit or miss?

Based on rules on pg 176 (assuming monsters have same rules as PC’s) the TB’s roll would be 12 – 2 = 10 so would miss. Please explain if that’s true or false using RAW with page number references if possible.

Sorry if this seems a simple question, but I’m just not sure regarding the ability scores for players vs monsters.

Best Answer

The twig blight hits.

Short answer: the "+3 to hit" notation in the twig blight's Claws action already accounts for everything that goes into the attack: proficiency, relevant stat, other modifiers (if they existed).

Modifiers to the Roll. When a character makes an attack roll, the two most common modifiers to the roll are an ability modifier and the character's proficiency bonus. When a monster makes an attack roll, it uses whatever modifier is provided in its stat block. (PHB p.194, emphasis mine)

Long answer: looking at the twig blight's CR (1/8) we know its proficiency bonus is +2 (MM p.8). Looking at the stated attack bonus (+3) we can see that it must be getting another +1 somewhere. Looking at the twig blight's stats we can see its attack must be indexed off of DEX (+1), not STR (-2). This makes thematic sense, as the twig blight's twiggy little claws could certainly have the finesse of, say, a dagger.

A close review of MM pp.6-11 and DMG pp.273-281 would provide all the detail one could possibly want on the subject. And more!


See also: how do I calculate an unarmed attack, specifically for slam?