Double-click to consume.
Double-click to gain a hero point.
A spiced, smokey concoction. Raven shamans make this, but nobody knows where or how.
— In-game description
The Raven Tonic is consumed to complete the hero challenge given by Corvin the Skaald at Durgar's Homestead located near Isenfall Lake in Snowden Drifts. Consuming it will provide a hero point and complete the hero challenge as well as transform you very briefly into a raven.