Ori and the Blind Forest: Definitive Edition: main story about 9 hours; story with some extras about 13.2 hours; 100% completion about 16.8 hours. These are IGDB player-submitted averages from 10 submissions, not a deadline or a prediction of your pace.
Source: IGDB player submissions
Community playtime data is not available for Ori and the Blind Forest: Definitive Edition yet.
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