If you like video games and you think you would be able to develop your own game, you should look for the best tools available, and we thoroughly recommend you to use Unreal Engine (UDK), also known as UDK.
It is the free version of Unreal Engine 3, one of the most powerful and best-known video game engines available to the date, and that was used in such well-known titles as Unreal Tournament 3 or Gears of War. It's not an easy-to-use tool, because we will have to spend quite a few hours working with the application before we get used to all the options and how to use each one of them.
The Unreal Engine 3 development kit
The development kit includes the Unreal Editor Toolset (a complete editor that we'll use for most of the work), AnimTree Editor (that will allow us to create the best animations) and Unreal Matinee (that will allow us to create film-like scenes), among many other technologies and tools.
If you're looking for a system with professional features, but you don't want to have to pay to create your own video games, don't think twice and download Unreal Development Kit now.