"Cedric Diggory was a Hufflepuff. His wand was pleasantly springy, 12 1/4 inches, single hair from a particularly fine male unicorn. Professor there is a note in our textbook concerning Cedric Diggory's wand. Quote:
Unicorn tail hairs
Cedric, Neville, Ron, and Draco all have wands with unicorn tail hairs in them. This is a bit disturbing because of the following exchange from PS15:
"Yeah," said Hagrid, glancing up, too. "Listen, I'm glad we've run inter yeh, Ronan, 'cause there's a unicorn bin hurt -- you seen anythin'?"
Ronan didn't answer immediately. He stared unblinkingly upward, then sighed again.
"Always the innocent are the first victims," he said. "So it has been for ages past, so it is now."
Cedric, like the unicorn, died.
Source: Harry Potter Lexicon