A common tactic on "highly compressed" download sites is to force you to complete a survey to unlock the password for the RAR file. These surveys collect your personal information, and even after you complete them, the password rarely works. The website owner makes money from your clicks, and you get nothing.
A 100MB file is roughly of the actual game. That is like trying to fit an entire library of 1,000 books into a single pamphlet. It cannot be done.