The Shadow are the forces of the Dark One. The Shadow has agents in every nation and organization that exists, but it also has special creatures and leaders of its own.
Trollocs are generally bipedal and humanoid, often with both human and animal features: human eyes but an eagle's beak, for instance, or a bear's paws and claws. They are huge in stature and extremely vicious. They are the basic shock troops of the Shadow.
They are tall and pale, muscular and serpent-quick, but they have no eyes, which does not impair their vision in the slightest. Myrddraal gain certain powers from the Dark One. They have the ability to cause paralyzing fear with a look and can vanish wherever there are shadows. They have few known weaknesses, one of which is that they do not like to cross running water. Myrddraal wear black armor with overlapping scales, and black cloaks which do not stir in the wind. In battle a Myrddraal wields his sword with great skill and incredible speed. They are able to move between, or disappear into, shadows, and mirrors only reflect a misty image of them.
Darkfriends, or Friends of the Dark, are normal folk who have secretly pledged support to the Dark One, whom they call the Great Lord of the Dark. Darkfriends, though not necessarily dangerous combatants, are also ubiquitous, as they can be and often are found just about everywhere. Darkfriends believe that when the Shadow triumphs they will be granted great power and immortality.
They are about the size of a small horse and look vaguely like a dog. Darkhounds typically run in packs of ten to twelve, though a pack may be as large as fifty hounds. The saliva of a darkhound is an acid that causes bruising and burns which spread quickly, and a few drops are enough to kill a person. The darkhound leaves no tracks on dirt, grass or snow; but if it steps on stone it leaves footprints.
A small subset of Darkfriends (of both genders, despite the name) actually donate their souls to the Great Lord. They become Gray Men, ordinary-looking folk who are, in fact, very difficult to notice, to the point of 'hiding in plain sight': to a person not specifically looking for one, a Gray Man carrying a knife is about as interesting as an old chair, the eyes will perceive them but the mind will write them off as nothing important. Their ubiquity and unremarkability is their primary asset, as they are sent as assassins against sensitive marks; frequently they do the deed without anyone even realizing they were there.
These are the thirteen most powerful channelers who served the Dark One in the Age of Legends. When Lewis Therin sealed the Dark One at the end of the war they were trapped in a dreamless sleep. However some say the seal is weakening and the Forsaken are once again touching the world. These are the leader of the Shadow and the Dark One's chosen.
The Shadow has begun to increase its activity. After the near complete destruction of the army sent to reclaim Malkier, flocks of ravens have started to attack travelers in the north. Bands of Trollocs also raid the new construction project being undertaken by the borderlands at Tarwin's Gap. Also, many different types of both Shadowspawn and Darkfriends roam the Blight