Ol' Nik

Trolls, are a sinister, clever, sadistic lot. They survive on the fringes of civilization, carving out little territories where they can. Trolls are tough. Only fire or magic seems to really hurt them, so one would think they would be bold creatures, unafraid of danger. But they are few, with an almost nonexistent birthrate. Male trolls tend eat what few children they have, as they see them as a threat to their territory. Cowards at heart, trolls only become bold when they see an opportunity. One such opportunity exists at the only known bridge across the Black River, Beyond the Wall.
Guarding this bridge is Ol' Nik. Know one is sure of his age, he has been at the bridge since the Great Collapse. Traders and surrounding surviving communities just became accustomed to "paying the toll" to Nik and for a time, his brother Klem. It's unusual for two male trolls to coexist in the same territory, but these two were formidable foes to any who tried clear the bridge of them. Many an armed group of peasants or traders had enough and made a run at the trolls. The result was usually quick and messy.
Klem has not been seen, however, for over 20 years, although Ol' Nik can still be heard talking to him. Tancred, barkeep at the Hole, has hinted that he is cause of Klem's disappearance.
For now, Ol' Nik still guards the bridge over the Black, extracting whatever he can from the few survivors Beyond the Wall. He takes gold, food, or the occasional lone traveller. Ol' Nik can the dumb old bridge troll when he needs to, but he should not be underestimated. He is a cold, calculating, survivor with quick talons and a sharp mind. And even sharper teeth....

Giants

Giants have been a feature of the lands Beyond the Wall, since before the wall was built, or the Empire itself. Calling themselves the Children of the Fallen, giants claim their descent from the Elder Times when demons and gods walked the world. Giants seem a bit cloudy on which group they can call their parents, but most agree they are not the race they once were.
Giants were both a nuisance and gift during the Empire's Golden Age. Settlements could just as easily been both prey to giants, or protected by them, depending on the creature in question.
The most commonly encountered giant Beyond the Wall seems to be either the Hill or Mountain variety. Neither is particularly bright, or evil for that matter, but they are easily tricked or bribed into vile acts by darker souls. They are greedy, however, and fond of drink, much like the dwarves they have been known join in battle. Indeed, dwarvish and giant are similar languages, a fact which dwarves tend to gloss over.
All of the Great Incursions have included giants in their armies; their great strength used to tear large sections of Wall down. The creatures are usually countered by the garrison by lobbing huge casks of ale or sheep into the giant's ranks. Once drunk, the giants tend to wander off to sleep.
Giants tend to stick to the highlands, but lack of food and stronger forces have been driving them more into the lowlands Beyond the Wall. Adventurers be wary when a long shadow passes their way.