Obfuscation Patterns

If I am thinking about the same MMO, then every client update changed everything. I am sure they used some custom obfuscations tools to even alter the client / server protocol.

The way how bots were done, was that you had to write tools that try to fingerprint interesting variables by their usage patterns in the bytecode. This was by no means an easy task. But with the frequent client updates manual reverse engineering only helped to understand the codebase, but to actually keep up with the client updates you needed to automate that work.