: PS2 game discs often contain massive amounts of "padding"—empty space or repeated data—to fill out the physical DVD. This is why a 4GB ISO can sometimes be compressed into a much smaller file; the compression algorithm essentially "deletes" the redundant padding while keeping the core game logic. The Reality of "100MB Highly Compressed" Files
Highly compressed games may occasionally crash during cutscenes if those files were improperly stripped.
Searching for "PS2 ISO highly compressed under 100MB patched" is common among retro gamers with limited storage or slow internet. However, here's what that search typically leads to:
(not promoting piracy) about this search term, here it is:
A standard compressed format used widely for PS2 and PSP games. Safety and Performance Warnings
