Real Time Strategy are very popular with gamers who want to immerse themselves in completely different environment. These games require strategy and resource management while continually advancing the player through harder and harder scenarios in other words, these games provide the player with a productive struggle.
For this challenge I played to of the suggested games. World of Warcraft II and Kingdom (Total War Battles). Both these games had similar characteristics. They require the player to build human resources (ie craftsmen), natural resources(minerals, food, construction materials) and develop increasing battlefield capacity(stronger and stronger soldiers). The other requirement for these simulations is time. Players can easily play for hours at end, losing track of time. Both of these games remind me of the Command and Conquer series of the mid 1990's which were very popular. I believe the real secret to this genre's success is that create a viable reality withing the player. You are whisked away to an alternate reality of sorts where you can quickly become assimilated.