Following this link you may find answers for many questions related to "cheats" or forbidden game client modifications.
All potential hacks are being fixed as they appear. We understand that it is a major threat and we keep attention to this matter.
We take care about hacks in our game. We improve server security with every patch. There are no working cheats that may affect the gameplay, only client modifications is possible.
All hacking software is phishing software in depth. It means that a program attempts to steal your account login and password, and in most cases your credentials are eventually lost.
We suggest you to avoid so-called "cheat" software.
However, if you suspect that someone does not play fair, you should report this player by right-clicking his name in the game.
Also please check the FAQ about your account security and cheats on our official site.