There is only one file type that uses the .W3G extension:
Warcraft 3 Replay File
Recording of a Warcraft III game; includes all activity of a scenario or match from start to finish; saved automatically in the WarCraft III installation folder; will be overwritten the next time a game is played if the file is not saved manually.
|Blizzard Warcraft 3||Paid|
Updated: August 5, 2007