[quote=@Raineh Daze]
As I said last night: the Dragonslayer is not antimagic. It does not automatically negate anything magical that it happens to come near. Even if its anti-demonic features and astral existence would help, that doesn't inherently mean it goes through an unknown enchanted substance like it's butter. FFS, for all you know, the staff simply has a shear strength beyond how it looks.
[/quote]

Except it's totally antimagic, and I can provide several examples of it cutting through magic and even hurting entirely ethereal beings.

As I said earlier, magic in the Berserk-verse isn't divided into subcategories of "demonic" and so-on. The Dragonslayer doesn't strictly affect demons, because demons in the normal sense aren't even a thing in the Berserk-verse. Either it comes from the astral realm or it doesn't.
And if we want to get really, really technical on how the Dragonslayer works, allow me to explain: it's soaked up so much magical blood it's starting to simultaneously exist in the normal and astral planes, essentially making it more real than anything else.

Also, it was never specified what material specifically the hammer was made of, so naturally I assumed steel or some similar alloy. The shaft is rather thin in the first place, and Guts can cleave through some seriously strong stuff with even just a normal sword.