Board Thread:General Mod Discussion/@comment-26322120-20160109210310/@comment-25101089-20160110003307

And some other possibly useful points: If an NPC is wielding a weapon, then they deal only 75% of that weapon's damage value (and only that amount; they don't have it added to one base damage). The 75% is because a full 100% made NPCs too powerful to be balanced. Originally NPCs just dealt a set amount of damage, but when I started adding more weapon types I changed it to account for the weapon so it was more interesting.

NPCs that don't wield a weapon usually do 2 base damage, but some that aren't meant to ever use weapons (Wargs, Trolls, Spiders) have a different base damage value. (As I said above, this 'base damage' is completely overriden if the NPC holds a weapon. If these Trolls or Wargs etc. were summoned with commands or edited in the save data files to carry weapons, they would instead deal precisely 75% of the weapon damage, as the other NPCs with weapons do).

And some NPCs have an 'extra damage' attribute that gets added on after the 75% of the weapon damage (or whatever amount of base damage) is calculated. Currently this is only used by the Dunlending and Uruk Berserkers, for which the attribute value is 2 and 1, respectively.

Also, remember that - for example - '6.5' means 6.5 half hearts, i.e. 3.25 full hearts. This was made possible in 1.6 when Mojang changed health and damage to floating-point values instead of integers.