Bella stumbled, but kept coming. "Thaumatic Dampening Field, Mudblood!"
She was on Tonks in a moment, turning a feint at the Metamorph Auror's head into a two-handed swing under the girls wand arm. Bella was ignoring Adrian and trying to get in too close for Tonks to get a second spell with her wand.
There was a commotion at both doors, the guards outside had noticed the problem.