Severus' shield was efficient, but not efficient not to stop an unforgivable. Reacting just in time, Emmeline threw herself to the ground and rolled away, feeling the strength of his Cruciatus curse as it brushed less than an inch from her. From a position from her back she threw several hexes in his direction. Stronger this time, aimed to cause as much pain as possible. Distraction as she got up, now bleeding from a cut. Glass on the ground she suspected.
She rolled fast, getting to her feet and throwing more hexes in his direction. She heard her robes rip as she got up but ignored them as she kept moving to avoid his curses and spells, throwing er own in return. Severus' shield was useful, but she could not keep it up and hex at the same time, and it would not help against those three spells she needed most to look out for. He seemed to have caught on, and it became useless. She would just have to be faster.