This FREE Rubble Set is available for download from http://www.badking.com.au/site/shop/environment/rubble-packby-badking/
(Please note you will need to sign in or create an account)
This set contains 64 Rubble parts in the form of an IMM Brush created for Zbrush 4R6 (compatible with R5 and R7), the original .OBJ files and a single .ZTL are also included.
Additional Note: By utilizing the ‘M’ key you can toggle between variations of the Brush Set.
And Much More!!!
http://www.badking.com.au/site/shop/environment/rubble-packby-badking/