FPE (Flash Project Encrypter) is a software for doing your flash projects, including encryption and obfuscation. Analyze the whole project and pick out the redundant classes. Make all SWF files encrypt to actionscript3. Obfuscate and inject random instructions to whole project and encrypt to the "Main" SWF file. With FPE you can encrypt and obfuscate multiple SWF files at one time. And the method calls between SWF and SWF will still right.