No real cheats for Guild Wars. Why would there be? It's an MMORPG!

Here's an Easter Egg for Guild Wars:

Joke Language in Language Menu

Open up the Menu, go to Options, and open the language menu. Here you will have your standard languages (English, French, German, etc.) and at the bottom there will be a joke language placed by the Developers called Bork! Bork! Bork!After using this language, everything will be in english lettering, but with strange spelling. You can undo this by reversing the process.