Massive Entertainment's Ground Control is not just one of the first but also one of the best and most well-designed tactical 3D RTSs, which means it has aged quite well in terms of controls, user interface and overall accessibility. For newcomers to the series, GC is especially worth a purchase if you're already a fan of World in Conflict, Supreme Commander and similarily action-packed strategy games from the last few years. And even by GOG standards, this generous bundle with both the original game and the great expansion pack is an absolute steal.