Remember the old adventure series Lone Wolf? Are there any interest for such a game using the rules published by Mongoose? How it is set up all depends on the number of people interested and... well a bunch of other things such as which types of game you want to play.
Magnamund is a planet in the universe of Aon which is the focus of battle between the powers of Good, among them Kai (God of the Sun) and Ishir (Goddess of the Moon), and Naar, the evil God of Darkness.
In the north-east of Magnamund's northern continent lies the realm of Sommerlund. Its people, the Sommlending, are devoted followers of Kai. There are those among them, known as Kai Lords or simply 'the Kai', who possess extraordinary innate abilities. Trained from childhood at the Kai Monastery, the Kai Lords are Sommerlund's greatest defence against Naar's agents.
Naar's champions upon Magnamund are the Darklords, who dwell in the scorched wastes of the Darklands, west of Sommerlund. This realm, inhospitable to most life, enables the Darklords to survive on Magnamund - though powerful, they are greatly weakened by the natural atmosphere of the world. Forced to enact their will at a distance, the Darklords wage war with armies of Drakkarim (humans devoted to Naar), Giaks (goblin-like creatures spawned in vast numbers), and other creatures, and are served by agents such as Vordaks (undead with psychic powers) and Helghasts (shapechanging undead).