[@Nightknight]
Well, they're significantly tougher than steel. High-powered rifles bounce off of Darquesse's shadows, and she was even able to block AP missiles with them. Not sure what you're vibro-blade's piercing capability is, but the shadows are also... well, shadows. So if you slice em in half, they just reform. She'd need to constantly slice them to create any sort of opening, especially with the covering her like a blanket.