StarCraft and StarCraft: Brood War are now free. Follow the links here to begin installing:

General:

Added windowed fullscreen or windowed mode; use Alt+Enter to switch between.
Added UTF-8 support.
Added cursor clamping in-game while windowed; unclamped in menus.
Added Popular Maps to streamline finding games or game types.
Added options to display actions per minute.
Added Observer mode.
Added opponent information when joining a game lobby.
Added autosaving for replays.
Added an option to display the game timer.
Added UPnP support.
Updated to a new OpenGL backend.
Improved gameplay responsiveness during multiplayer by increasing turn rate to match LAN speeds over Battle.net.
Improved UI layout in Battle.net sections.
Improved behavior of available lobbies within the ‘Join Game’ section.
Improved compatibility with Windows 7, 8.1, and 10.
Improved anticheat capabilities.
Improved installation and patching performance.
Mac Beta support now available for 10.11 and up.

Bug Fixes:

Fixed palette issues to correct rainbow water, 80s Kerrigan face in the loading screen, and other graphic glitches.
Fixed problems with LAN game discovery.
Fixed IME support and other text artifacts in Battle.net menus.
LAN and Legacy Battle.net fixes.

Known Issues:

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