However, a lethal stare isn't the only weapon that the Basilisk is bringing to bear...
Why is this important?
Because anyone would turn to stone if they specifically looked at her face, not just any part of her body. Thus, it could kill her before it had the chance to look at her face. Indeed,
True, in some versions, she turns anyone SHE looks at into stone, but even if that was the case in the battle, she'd still be at a disadvantage.
Thus, I conclude...