Aerondight is a silver sword that does a bunch of damage, but doesn’t have the usual stats. Instead, it has some unique abilities. Every time you hit an enemy, your damage will go up by 10%. As time passes, you’ll lose charges. Same goes for getting hit. When the sword is fully charged, it deals critical damage with every swing.
The other ability increases the sword’s damage permanently each time you kill someone while it’s fully charged. The threshold for this increase moves up as you level up your character, letting the weapon practically level up alongside you.