Why did Zobrist leave a clue?
137163
Why did Zobrist leave the trail to the virus in the first place?
11848
Why did Voldemort reveal himself at the end of OotP?
131835
Why couldn't Voldemort trace Harry's residence and kill him?
118137
Why was triwizard tournament continued even when Dumbledore knew that it was dangerous for Harry?
80463
Why didn't the Hogwarts ghosts know about the Chamber of Secrets?
103519
The mystery of the tagged answer - and more
115749
Java Puzzler- What is the reason?
121243
Why didn’t anyone dial Abydos before Daniel solved the mystery of the seventh symbol?
113957
Why is it possible to conclude everything from a false statement?
109222
Why didn't Dumbledore leave Harry a big pile of basilisk fangs?
22549
Why couldn't Ellie's experience be corroborated by simply re-using the machine?
72787
Why are we so sure about Map results?
146283
Why didn't Harry, Hermione, and Ron discover the Bubble-Head Charm in advance of the second task?
92178
Why didn't Isildur's Heir come forward sooner?
113986
Fermat's Last Theorem: implications (there is no new proof)
135348
Is Zitterbewegung an artefact of single-particle theory?
30814
How is "Can anyone tell me how can I solve this" wrong?