Disciples 2 is an excellent, turn-based strategy game that takes elements from the Heroes of Might & Magic Series and transposes them into a brand new fantasy world. The game can be exceedingly difficult at times, but in a fair way that encourages you to plan your battles better.
Additionally, this is a fantastic value for the original game and its expansion packs. I recommend downloading the demo version of the game before buying because it certainly isn't for everyone, but if it's for you, it is a fantastic investment with many hours of gaming goodness to be had.