BioShock 2 Remastered: main story about 11.7 hours; story with some extras about 13.8 hours; 100% completion about 35.3 hours. These are IGDB player-submitted averages from 8 submissions, not a deadline or a prediction of your pace.
Source: IGDB player submissions
Community playtime data is not available for BioShock 2 Remastered yet.
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