Elder Scrolls IV: Oblivion

A lowly prisoner has been cast into the depths of the dungeon in the Imperial capital of the province Cyrodiil. The fate of this prisoner suddenly changed when Emperor Uriel Septim descended into the prison with his guards, fleeing from unknown assassins who have already slaughtered his children. But even an emperor cannot escape his destiny. Before the last assassin delivered the lethal strike, the old emperor entrusted the prisoner with the Amulet of Kings and asked him to find his illegitimate son, the last of the Septim bloodline. The Septims and the Amulet are the last barrier between the continent Tamriel and the dark dimension of Oblivion, and the delicate balance is threatened by the Daedra Prince of Destruction, Mehrunes Dagon, the prisoner being Tamriel's only hope.

The advancement system is based on skill usage. When the player repeatedly uses one of the skills, it improves. NPCs offer training (for a price) to help in advancing to the next stage. In time the protagonist can become an Apprentice, Journeyman, Expert, and Master and gain certain bonuses for the skill. The skills of the foes are "leveled" to be approximately equal to or slightly above those of the main character.

There are numerous side quests that help the hero advance his or her abilities as well as gain fame. The player is free to roam the world without a particular goal, exploring towns, forts, caves, mines, and old temple ruins. Visiting shrines scattered around Tamriel grants the protagonist specialized skills, some permanent and some temporary.

Weapons and armor wear out with use and need to be repaired either with the help of special non-playable characters or by using an appropriately trained Armorer skill. Enhanced items (weapons, armor, clothing, rings, amulets) abound in the game for protection, resistance, reflection, and special activities like walking on water, exploring underwater, becoming invisible, or lightening the load. It is possible to open the gates to the Oblivion realm to grab their sigil stones, which can be used to make enhanced items. Higher-level mages can create their own spells and enchant weapons, armor, and clothing using filled soul gems in addition to sigil stones.