Kozilek Brood- Skin isn't pierced by a knife

She swung the knife forward, slinging all her strength and momentum with it, aiming to spill open whatever innards the creature might hold.

The weapon reverberated with the unexpected impact to the Eldrazi's outer mass, sending shockwaves down her arm and through to her teeth. She reeled, her numbed fingers dropping the knife. Behind her, she heard Denn scream and run toward her.

(Reclamation)