Dark trolls (AKA Dark forest trolls) are a species of trolls living in subterranean regions or dark regions. They are the tallest race of trollkind.
There is currently no evidence or proof if the dark trolls have ever formed a nation or any civilization. Their numbers are so low, yet it seems they are from one single troll tribe.
When Grom Hellscream first arrived in the night elven forests of Ashenvale, he found a destroyed dark troll settlement. Later, dark troll settlements were destroyed by Tyrande Whisperwind, leader of the night elves and Malfurion Stormrage, a famous night elf druid and they desrtoyed their army during thier search for the Druids of the Talon. A tribe/clan of Dark trolls joined the night elves named the Shadowtooth Clan during the Battle for Mount Hyjal.
Dark trolls are usually a subterranean troll race, only coming up to the surface at nighttime to hunt. They have tribal structure in which physical power and cunning are held in great esteem. Tribal shamans of spiritual guidance and divine magic when reasonable. This is similar-but far more primitive-in social structure the jungle troll race, the most civilized of trollkind. Though dark troll culture is similar to their forest troll cousins they are much more violent. It has been speculated that dark trolls have less intelligence then the other troll species. They have recently befriended blood elves. They have also become allies with the goblins due to their similar hobbies of stealing from pirates.