Axiomatic Weapon

Weapon (any weapon), rare

You gain a +1 bonus to attack and damage rolls made with this weapon. When you hit a chaotic aberration, dragon, fiend, or undead with it, that creature takes an extra 2d6 force damage. (At the Gm’s discretion, certain especially chaotic creatures might take this damage even if they have a different creature type.)

Axiomatic weapons are usually crafted with icons, runes, or symbols from a lawful-aligned deity.