Bioshock Infinite made serious waves with its Inception-esque story, fast-paced gameplay, and stunning visuals. More than that, it uses the Konami Code in a very creative way.
Bucking the trend of using the code to make their game easier, publisher 2K Games decided to use it to make the game harder. Punching it in at the game’s menu screen unlocks 1999 mode. This mode makes the enemies harder and your health bar smaller for the entire campaign.