- Harry Potter: "What? Isn't there just a password?"
- Luna Lovegood: "Oh no, you've just got to answer a question."
- Harry Potter: "What if you get it wrong?"
- Luna Lovegood: "Well, you have to wait for somebody who gets it right. That way you learn, you see?"
- — Harry Potter and Luna Lovegood discuss how to enter the Ravenclaw common room[src]
The eagle door knocker of Ravenclaw Tower is a bronze, eagle-shaped knocker on the door to the Ravenclaw common room, and acts as the Tower's guardian in much the same way as the Fat Lady does for Gryffindor Tower. Unlike the Fat Lady, however, the knocker does not ask for a password, but asks a thought-provoking question that must be answered in order to enter. The questions differ constantly, asking puzzles and riddles. Such questions include:
The questions typically have no straight forward answer, but require a level of reasoning or logic behind them that reflects the wisdom of the hopeful entrant to the tower. The knocker often compliments successful entrants for their skilful logic, but tends to go quiet if the answer is wrong. The question will remain the same until it is answered. The knocker will not let anyone in who does not know the answer to its question, though if someone else answers the question, one may enter with the help of another who answers correctly.
When Luna Lovegood and Harry Potter attempted to enter Ravenclaw Tower just before the Battle of Hogwarts with the purpose of seeing a statue depicting Ravenclaw's lost diadem, the knocker waylaid them with a question to which Luna answered.
Moments later, the knocker halted Amycus Carrow, who could not answer its question, and attempted to blast and bludgeon his way past the door instead. The knocker's question was answered correctly by Minerva McGonagall, whom Carrow demanded open the door.
The knocker has a soft, musical voice, and seemingly pays little heed to any sort of dialogue other than that of answering its question, again a difference to the Fat Lady.