The Horn of Cenarius

After Cenarius fell, his horn remained on Moonglade under the watch of ancient guardians. When the Burning Legion returned in the Third War, the priestess Tyrande Whisperwind recovered it and used it to wake Malfurion Stormrage from his long dreaming. Malfurion in turn sounded it to rouse the sleeping druids of the Talon and the Claw.

At the climax of the Battle of Mount Hyjal, Malfurion blew the horn once more. Thousands of ancestral spirits answered and swarmed Archimonde, destroying the demon lord at the foot of the World Tree, though the power unleashed left Nordrassil wounded.