There are about 400 technologies to research and the possibility to construct over 2,000 unique units. It's like an erector set on steroids. Like most RTS games of late, queuing is available as well as constant production. The battlefield view can be fully rotated and zoomed. There are 3 very large campaign maps for a total of 32 missions as well as 24 quick missions for those of you who need a quick fix.
Missions usually consist of seizing enemy territory and grabbing new technology.
Once you have the captured technology, researching will make it available for further enhancing your military or engineering might. Some of the missions are also contiguous, so the better you do in the previous mission can bode well for your subsequent missions. For these linked missions, you also carry your units with you so having these veteran units can turn the tide of battle in your favor. Especially noticeable in linked missions. On one hand, I like the idea because it prevents players from amassing a huge force or hoarding resources prior to the next mission.