: DayZ frequently goes on sale. Purchasing it officially ensures you get automatic updates, access to the full DayZ Workshop for mods, and secure, malware-free files.
: DayZ is fundamentally a multiplayer survival game. "Highly compressed" versions are often cracked (pirated) and cannot connect to official Bohemia Interactive servers. You may be limited to a few unofficial, often unstable, "cracked" servers with much smaller player bases. Dayz Highly Compressed PC Game
If you are struggling with the 25GB+ download size of DayZ, consider these safer alternatives: : DayZ frequently goes on sale
: Groups known as "repackers" take the official game files and compress them into much smaller installers. Dayz Highly Compressed PC Game