Bricks are classified into three different sections: login pages, file upload pages and content pages.
Each login page has its own security mechanisms. Your mission is to break them and get in.
Each file upload page has its own security mechanisms. Some pages allows you to upload only some specific picture files. Your mission is to break them, upload shell scripts, execute them and gain access.
Content pages displays contents based on user inputs. In some cases they have their own security mechanisms too. Your mission is to break in, inject you code, execute it and gain access.