Lone Wolf Saga is a digital implementation of the Lone Wolf gamebook series created by Joe Dever. The digital implementation includes automated random number generation for the combat system, automatic health tracking, as well as inventory tracking and management.

Magnamund, a planet in the universe of Aon, 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 defense 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 their 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).

At the Kai Monastery is a young initiate, given the name Silent Wolf. On the feastday of Fehmarn, when all the Kai Lords gather at the monastery, Silent Wolf is sent to cut wood from the surrounding forest as a punishment for his inattention in class. While he is gone, a surprise attack is launched from the Darklands at several places across Sommerlund. The Monastery is assaulted and the gathered Kai Lords massacred. Rushing back from the woods, Silent Wolf is knocked out by a low-lying tree branch (in the Legends of Lone Wolf novelizations based on the books, it's implied that the branch was placed there by a demi-goddess called Alyss so Silent Wolf would be spared the attack). When he awakes, he finds himself the only survivor. The last of the Kai, he renames himself Lone Wolf and sets out for the capital to inform the King of the loss of the Kai.