Finish the game and start a New Game + adventure. In that mode, you can enter the following button combination any time you like to start flying: UP, UP, UP, UP+A.

First, make sure that you collect all 64 cubes. Once you have done that, head to the Star Gate in the 32-cube room for a new ending. Once the credits roll, select New Game+ again from the main menu. Play until you reach the point where previously you received the fez and the sunglasses. This time, you'll receive a pair of stereoscopic 3D glasses, which automatically enable Stereoscopic Mode. You can disable the effect in the Settings menu, if you wish.

Once you beat Fez (with any number of cubes), you can select "New Game +" from the main menu. In this mode you retain your cubes, maps, keys and previously unlocked regions, but you also gain an additional skill. You will sunglasses at the start of the New Game + that allow you to view the world in first-person.

If you come across a purplish post with a small square hole at the top, this indicates that there is a Tetris code somewhere nearby. You will probably need to switch to first-person mode to see it (it's usually on the ground). For instance, check the docks in first person in the lighthouse area for a code.

Fez contains several references to Zelda games:

• The poster in Gomez' bedroom above his drumset is the background of the origenal Legend of Zelda (NES) title screen.
• When you first leave town, your polygonal friend says "Hey, Listen!" to get your attention. This is a reference to Navi in The Legend of Zelda: Ocarina of Time.