Sir Jon Emberfall is one of the city’s more wealthy nobles. He’s used his wealth wisely, spending extra on public works while ensuring his wealth continues to grow. Never married, without an obvious protege, and definitely on the far side of middle age, some have started to wonder aloud what will happen to his money when he passes on.
In the meantime, he’s showed an interest in magic and the occult. He hires adventurers to collect rare magic items.
As a friendly faction, Emberfall’s a decent man with a natural head for investing and a curiosity about magic. Collecting rare magic items (particularly those forest-related) is an idle hobby, and he’ll hire the PCs to retrieve several, and he pays well.
He does have an ulterior motive, though: he’s looking for an heir. If any of the PCs particularly impress him, he will approach him or her privately and ask after their affairs. If he passes away in the game, that PC will find him- or herself heir to the Emberfall fortune. This may bring more problems than the PC expects.
As a foe faction, Emberfall’s secretly become indoctrinated in the Brothers of Talos, a dark cult. He uses his publicly-known artifact collection partially as cover; every fourth or so item he has collected is actually part of a ritual aimed at summoning and controlling a powerful demon.
Emberfall’s gothic manor consists of four levels, of which the fourth contains his most prized items. PCs attempting to raid it will have to contend with his dozen or so goblin servants and about half a dozen gargoyles and animated statues set up at key points in the manor’s layout. Google a manor layout that you like and just introduce goblins or gargoyles at reasonable points as the PCs explore.