The listing, Sudden Strike Gold (Steam Key) has ended.
http://store.steampowered.com/app/612300/Sudden_Strike_Gold/
ABOUT THIS GAME
Set in World War 2, Sudden Strike offers revolutionary real-time-strategy gameplay. Command Russian, German, French, American and British armies in large scale battles including urban warfare, beach landings and aerial invasions. Whichever tactics you choose, you will find it in Sudden Strike!
Features
Up to 1000 units per scenario including historically accurate tanks, artillery, infantry and aircraft
Gigantic maps offer unparalleled strategic depth and tactical choices
Destructable terrain, bridges, houses, fortifications and trees
Build fortifications and pontoon bridges
Contains the original RTS classic "Sudden Strike", "Sudden Strike Forever" add-on and "Total War" map pack
Contains map editor