Dawn of War is a combination of fantasy and science fiction based on the famous Warhammer 40,000 tabletop game, beautifully rendered in 3D. There is a solid mix of units and none of the playable races have been given an overwhelming advantage. It is a nicely polished game with an active community, and Relic has released a steady stream of expansions for the title, including Winter Assault, Dark Crusade, and most recently, Soulstorm. The Platinum Edition comes with the Winter Assault and Dark Crusade expansions.
This is a classic 2D sci-fi RTS from Blizzard which still has a large and very devoted following. You play as one of three different species, each with their own unique units and special powers, in an effort to overpower your opponents. Although it has been overshadowed by the release of StarCraft 2, the original remains one of the most popular RTS games played in video game competitions, especially in Korea. The Battle Chest version includes the Brood War expansion, and it supports up to 8 players over Battle.net.
The Red Alert series, with their twisted alternate timelines, are perhaps the quirkiest games in the Command & Conquer franchise, which has never really aspired to any sort of realism. Red Alert 3 features a wealth of outlandish units, including war bears, shrink beams, mini-subs, and sci-fi ninjas. It also has a considerable amount of naval combat, and the single-player campaign accommodates co-op play quite nicely. Voice chat is built-in, and you can skirmish with up to 6 players online.
For space strategy on a large scale, the often overlooked Sins of a Solar Empire has a lot of appeal. It is real-time, but the pace is very leisurely, allowing you to control numerous fleets of ships quite easily. Matchmaking for multiplayer is done through Ironclad Online, supporting up to 10 players (5 vs. 5). Multiplayer matches can take a long time on the larger maps, but they can be saved and played over several sessions.
Developed by Ensemble Studios, which was disbanded in 2009, Age of Empires is an iconic series in the RTS genre. The games have a historical basis, with players adopting the role of a civilization and trying to overpower their opponents. Age of Empires 3 was released in 2005, followed by The WarChiefs expansion in 2006 and The Asian Dynasties expansion in 2007, all of which are included in the Complete Collection. It's the most graphically current game in the series, and features online or LAN play using a utility bundled with the game.