This item is acquired in-game. See its sources below.
Chance on melee attack to grant Demonbane, increasing Strength and all damage against Demons by 10% for 15 sec. If you score a killing blow while this effect is active, its duration is extended by 8 sec up to the original duration.
Spell effects bound to this item, from first-party game data.
Gronntooth War Horn is not traded on the Auction House, so it has no live market price. Its first-party game data (identity, effects and sources) is read from the official World of Warcraft client build.
Read from the World of Warcraft client build files.
TheWoWDB