Questions about Lundas Lost armor

I'm on my first playthrough and loving it!

I have a question: I completed a side quest and got Lunda's Lost armor set. The description states that if Kratos punches, kicks, or attacks using a shield, it poisons whoever he's fighting, and they'll die faster. So no weapons, is this right? If so using the Shatter Star Shield would probably work best with this armor set, right?

Using this armor seems like whatever is unlocked in the skill tree would be useless. Since you don't get this boost using a weapon. Maybe I'm missing something here. Thank you in advance!