Even though Nova Covert Ops is a single-player experience, the modern StarCraft II client frequently checks for ownership licenses via Blizzard’s servers.

Because StarCraft II is tied to Battle.net accounts (which often contain Hearthstone cards, WoW characters, or Overwatch skins), many fake "cracks" are actually phishing tools designed to steal your login credentials.

Because StarCraft II is a competitive multiplayer game, the client updates often. Most "cracked" versions of the game are tied to a specific, outdated version of the client, meaning you lose out on balance patches, bug fixes, and engine optimizations. The Risks of Using Cracked Software