Oni features several secret areas and easter eggs that reward exploration. Some levels contain hidden rooms with extra health or stamina pickups, while others offer unique vantage points or shortcuts. For instance, in Chapter 05: 'TCTF Headquarters', a hidden office containing a developer's note can be found by punching a specific section of a wall in the archives. Another notable easter egg is the 'Bungie Room' in Chapter 09: 'Syndicate Mountain Base', accessible by performing a complex sequence of jumps and dodges near a specific ventilation shaft. These areas often provide a glimpse into the game's development or offer a moment of levity amidst the intense action.
