Halo Custom Edition and the Halo Editing Kit Released Halo Custom Edition is a multiplayer only, standalone version of Halo for Windows. This unsupported version of the game introduces a host of new features including the ability to play user-created content, which can be created with the Halo Editing Kit. Halo Custom Edition is meant for owners of Halo for Windows and requires a retail Halo for Windows CD and CD key to install. The Halo Editing Kit (HEK) allows fans to create their own custom content for Halo Custom Edition. This powerful set of tools, source material and tutorials provides users with an unprecedented amount of freedom in the development of new game content. The Halo Editing Kit requires that you have Halo Custom Edition installed. Visit the Gearbox Software Web site for more details as well as download locations for the Halo Editing Kit.