The length of The Elder Scrolls IV: Oblivion varies greatly depending on your play style and how much content you want to experience:

• Main story only: Completing just the main quest takes about 14 to 27.5 hours in the original version, and around 15 to 20 hours in the Remastered edition

• Main story plus side quests: Playing through the main quest along with many side quests typically takes between 40 to 80 hours, with the Remastered version averaging about 44 to 80 hours depending on how thoroughly you explore

• Completionist playthrough: To achieve 100% completion-finishing all quests, exploring every area, and maxing out skills-players often spend 78 to over 150 hours, and sometimes even over 200 hours if playing leisurely

• Expansions: The expansions like Knights of the Nine and Shivering Isles add significant playtime, often 10 to 40+ additional hours depending on how much you engage with them

In summary, if you rush the main story, Oblivion can be completed in about 15-20 hours, but a full, immersive experience with all content can easily exceed 100 hours, with some players spending upwards of 200 hours exploring the vast world of Cyrodiil