[quote=@Raineh Daze]

Exact quote: "By slaying countless monsters, the sword has taken on magical properties, and can now harm magical beings that can't be hurt by mundane weapons". It isn't explicitly negating [i]any magical anything[/i].

[/quote]

That was clearly a fancy way of saying "The sword can hurt magic stuff now." Mundane, nonmagical weapons can't typically hurt ethereal spirits or cut through mana; the Dragonslayer can do and has done both.