She symbolizes blindness. She is often depicted with 4 or 10 arms.
(Half) Skull (Kapala) :
It symbolizes the cycle of life and dead.
Spear (Skula) :
This is an indestructible weapon
Sword (Khadga ) :
It is symbols of enlightenment (wisdom), used to destroy ignorance, the enemy of liberation from the bonds of worldly attachments, hence of continuous misery.
Battle axe (Parashu):
The axe symbolizes the victory on ignorance/ evil
Riding Animal :
Owl or corpse.