Searching for "XCOM.Enemy.Unknown.Complete.Pack.zip" (with quotes) reveals it on:
: Autopsy aliens and salvage their wrecks to unlock laser weaponry, plasma cannons, and advanced flight suits. Technical Note When extracting a of this size, ensure you have approximately 15–20 GB File- XCOM.Enemy.Unknown.Complete.Pack.zip ...
– GOG sells XCOM: Enemy Unknown – Complete Edition completely DRM-free. You get an offline installer (no .zip, but a safe .exe). You can back it up anywhere. Searching for "XCOM
XCOM: Enemy Unknown | Complete Pack (PC) - Steam Clave - G2A File- XCOM.Enemy.Unknown.Complete.Pack.zip ...