From the Site:
Games invent worlds with rules, and in these worlds, secrets are magic. Tricks and codes are the perfect way to appendage value to a game without having to mess with the basic flow of it. Easter eggs about as old as gaming itself, adding intrigue and establishing a playful line of communication between player and designer. The most fun secrets lead to unlocked game elements, rewarding you for your hard work playing (or looking up codes) with new tools and functions, but the best of those are the unlocked characters. The examples below show three famous badass unlocked characters, each accessible in totally different ways, each interacting with the player in different ways as well.
