When you see the term "highly compressed" attached to a PS2 ISO file, it refers to the process of drastically reducing the file size of the original game disc image. The goal is to make the file easier to store and faster to download, especially for users on limited data plans or with low hard drive space.
These files are often stored on platforms like MediaFire or Google Drive. Dragon Ball Z Budokai Tenkaichi 3 Highly Compressed