can anyone tell me if Toughness counts while using "-x hit points" thing?

for example if there is a Toughness 1 / 1HP unit and I hit it with "We need your blood" does the "- 1 HP" go into Toughness?

on one hand it seems to me that it goes around Toughness, as Toughness cancels damage and "-1 HP" is not damage, but on the other hand this effect seems very strong (not that I don't like it

No, Toughness does nothing vs HP reduction.

Bigger question is why are you playing 1HP units vs DElves ?

Thanks!

I'm not playing against DE - I'm leading them to victory