Generations ago, Oro was ruled by the Tyrant. The Usurper was his vizier, master of the bureaucrats who ran the city-state. Oro was tightly controlled, with strict curfews and harsh punishments, but it was efficient and stable. And the Tyrant was a master of war, leading from the army's vanguard, hewing about with his headsman's axe, felling ten or a hundred times more enemies than the next man. On the battlefield, the Tyrant was the Lion, death incarnate.
It's said that the Usurper saw the plight of the people and slew his master, but history has a well-known victor bias. And yet... the people of Oro still call their ruler the Usurper. His vassals call him the Usurper. His soldiers call him the Usurper. And the Usurper himself doesn't seem to care. Some openly pine for the Tyrant, but others claim that the safety and stability of Oro in those days was not worth the price.
Whether the Purifier saw an opening after the Tyrant's death, or whether war had been planned all along... no one can say for certain. What is certain is that the war was far bloodier than any fought under the Tyrant. The Usurper led from far enough back that he could barely be said to have taken the field at all. The Purifier watched from high above the field, reveling in the destruction, seemingly satisfied with a war that ground to a standstill and left the Cascada range littered with the corpses of the fallen. Many in Oro think her mad. Her title seems at travesty, her nation, Edani, barely controlled and rife with corruption. When the whispers of insurrection in Edani began to spread, those old enough to remember the end of the last war only shook their heads. The Purifier, they said, would lose Edani. It was only a matter of time.
But the Usurper seems bent on maintaining this fragile -- if long-standing -- peace. If this is part of some greater design, none on the streets have any inkling what it might be. Rumours abound: he's seeking true immortality, goodhood; he intends to attack the Watcher to the south; he has uncovered the true purpose of the Shroud, and waits for it to envelop his land so he can put it to use.
Marshal Grey is a Shroudborn, master of Oro's mercenary companies. It's from him who you received your commission and to him who you'll report at its conclusion. Rumours say he was born eladrin, but it's also known that birth in the Shroud has the greatest effect on eladrin, rendering them barely recognizable to members of their own race. Rumours also say that he served under the Tyrant, in the great war between the Tyrant and the Deceiver in the north. Skin impossibly pale, eyes blank as slate, none can gauge his age or the truth of these rumours. What is unquestioned is his prowess. When challenged to single combat in a great hall among soldiers and mercenaries, he waited with open arms for his opponent to charge... and then the Shroud erupted from him, and both vanished into a howling abyss. A few moments later, Marshal Grey reappeared in the centre of the arena, alone, blood on his blade.
No one ever challenged him again.
Marshal Grey always personally approves the Cascada Pass garrison. He offered you little advice, saying only: "Get acquainted with the keep." When you asked others about the keep, you were greeted with shrugs.
"Marshal Grey always tells them that."
The Allabar entry in MM3 inspired me initially, so I took that concept and applied it to the premise of the 3.5 setting Midnight, which is like Middle-Earth if Sauron won the War of the Ring. In place of Ringwraiths, I have Myth-style Fallen Lords / Dark Sun Sorcerer-Kings who nominally serve Allabar, but mostly scheme against each other. Then I added One Bad Egg's Shroud concept, a mysterious fog from the far north that is gradually reshaping the world. 
