How are Attack Bonus Calc for Monsters

[ForbidenMaster]

Same thing with AC. The Kobold Skirmisher has AC 15 wears hide armor and a Dex 16 (+3) where does the 15 come from? What if I wanted to give him chain mail armor. The rules in the dmg say take the ac - 10 - dex this number is the effective armor bonus. If that number is lower then the new armor bonus the creature will benefit from the new armor. So if I take that example 15-10-3 = +2 this does not equal the armor bonus of hide.

Which is why they dont just say subtract the bonus hide provides and add the bonus for chain mail. Its convoluted, but its supposed to work, and it really isnt to much math.

 

[Eytan Bernstein]

Monster role + Monster level + DM fudge factor.

PCs add half thier level to everything they do, but get to add all kinds of fiddly power and feat and race and enhancement bonuses to them. Monsters just add 1 per level, plain & simple.

This gives your PC a good guideline to shoot for. If you're not advancing all your numbers by one per level, in general, you're below par. If you're generally keeping up with a 1-per-level boost, you're keeping up with the treadmill. If you've got a number advancing at better than one per level, you're doing pretty good.

It's pretty much determined by role and level. Each role (brute, soldier, lurker, skirmisher, artillery, and controller) has a base, and the monster's level is added to this. Some monsters are better than others at hitting AC, and others are better at hitting the three defenses. One of these days, I'm sure someone will put out a spreadsheet that calculates this for you.