The forest of Taur-na-Torogrim, or 'Forest of troll-men' in Sindarin), is cursed variant of the Far Harad Forest, controlled by the Half-trolls of Pertorogwaith.
The region centers around a river flowing from a vast inland lake in the eastern Far Harad Grasslands through the Far Harad Forest into the Pertorogwaith region. The river banks were once home to a Taurethrim tribe that established a flourishing city called Kimen Kâh. At some point in time, the spawn bred by Sauron rolled over these lands to leave no man or structure standing. The devastation this lead to is still ominously present in every visible aspect of the once so lush and prosperous forested area.
The dominant presence of half-trolls ensures that trader and Bandits stay away. The Taurethrim send out incidental expeditions to this forest, possibly in some attempt to scare off the demons that dwell here, or just to hunt down any other enemy force that may pose a potential threat to their distant jungle based lands.
Upon entering this region a players is granted the achievement "Forest of Demons".
Next to the standard, most common, variant, the following biome variants can be found here:
Flowers - A version of the biome with an abundance of flowers.
Light Forest - A lightly forested version of the biome.
Hills - A hillier version of the biome.
Forest Hills - A forested version of the hill variant.
Clearing - Areas where trees are less abundant than in the surrounding lands, but the soil is not particularly poorer.
Wasteland - Wasteland is a very barren biome and can vast stretches of the terrain consist of barren rock. The soil is generally very poor and vegetation is sparse. The landscape can both consist of flat plains and rolling hills.
Structures
Apart from scattered ruins of what seem to have been Taurethrim structures, there are no structures in this region.
The half-trolls passing by leave nothing but piles of waste and skulls in their track. They don't even set up camps.
Mobs
Half-trolls dominate this region, but do not inhabit it. Regular patrols of the following units can be encountered here:
Half-troll - Vicious savages that look like a mix of Men and Trolls.
Half-troll Scavenger - Half-trolls that sell odds and ends to the weary traveler. Unlike every other trader, they will attack those with negative Half-troll alignment with their poisoned daggers.
Like in their homeland, Pertorogwaith, the half-trolls carefully ensured they are topping the food chain and eradicated any land based competition, and many of the most common prey animals of Far Harad. This made them leave only Crocodiles and a few meaty, and the most hardy, herbivorous species to live among them:
Gemsbok - Passive antelope-like mobs. Their hide makes very nice looking armour.
Rhino - Ridable mob that will attack when threatened.
Vegetation
Since the Half-trolls took over this area gradually lost any resemblance to the neighboring Far Harad Forest. The vegetation is, like its flora, very similar to that of the Half-troll homeland Pertorogwaith. Acacia and desert oak are the predominant tree species, but many of them are dead. Some patches of grass and dead trees are blasted or covered by boulders or piles of randomly spawned waste blocks. Ground vegetation includes wheat grass, thistles, and clovers. Giant Baobab trees also spawn in the forest variant.