So.. I came across a 260MB (or so) .cso file of a game that is usually more than 1.8GB. It runs perfectly fine after playing it for multiple hours. How the heck was that achieved? o__O I tried converting files with some apps, but only get like 30 or so MBs of compression.
Is there some kind of APP that does this, or is it just the work of really crafty hackers/programmers?