PLEASE NOTE: The pdf's of the various rulebooks are currently unavailable. Pendraken Miniatures have recently purchased the rights to the BKC rulesets and will be working on the rules over the coming months, with a view to a new print run towards the end of 2015. The pdf's of the rules will become available again at this time.
The books are also still available as monochrome perfect-bound books from Lulu.com.
In the meantime, you can still purchase access to the Battlegroups Online feature, which allows you to build custom armies for use with the BKC rulesets. Simply select the access you would like to purchase, then click the 'Order Selected Products' button to place your order. Once you have paid, you will receive an email to confirm your purchase and you will now be able to login and use the Battlegroups Online service.