However, just as Dumbledore's voice fell, another wave of magical energy swept out from the room.
Before Dumbledore could even react, the magical power had already surged past, instantly sweeping through the entire Hogwarts Castle.
Dumbledore's expression changed drastically. "An Auror-level magical wave! Heads of houses, return to your respective common rooms immediately, escort all students out of the castle, and maintain order!"
Chapter 24