Spore - Civilization Stage
During Spore's civilization stage, things really start to pick up. The complexity increases significantly along with the level of difficulty. The game is clearly moving you along steadily as it adds more layers with each stage progression.
Now you are more than just your creature. You are an entire civilization! Your customization options expand enormously at this stage as you get to create towers, factories, entertainment complexes, houses, and vehicles (land, sea, and air). You also must plan the layout of buildings in your cities to maximize happiness and production. You even get to adorn your creature with articles of clothing and other accoutrements.
This stage is also RTS-like, and it is significantly more complicated than the Tribal Stage. Detractors should hopefully be able to see the progression and how the game is trying to ease more casual gamers into the flow of things. Not everyone has played 10 RTS games before Spore, so bringing them along one step at a time has its merits.
Conquer the Planet... Again!
Once again, your goal in this stage is to dominate the planet. In addition to the standard military or diplomatic means, you can also take over other cities through religious conversion. Functionally, religious conquest is very similar to military conquest, but the process differs noticeably and the visual effects are quite appealing. I will not spoil the fun by saying any more, but I personally find religious conquest to be the most entertaining.
The replayability of this stage is high as the different types of planet conquest are each enjoyable in their own way. Some are harder than others depending on your own playstyle and the types of neighbors you randomly end up with. You also manage resources more seriously in this stage than in any other, and you are introduced to the most valuable commodity in the universe: spice.
As every reader of Dune knows, "the spice must flow", and this is certainly true in Spore. You must control as many spice mines as possible to fund your burgeoning empire. Your first conflicts with other "nations" (for lack of a better word) may very well be caused by competition for spice mines.
There are many exciting moments during this stage. When you unlock sea vessels or airplanes your people rejoice at the technological marvel. If you go the military route, using nuclear missiles on another city is quite impressive. If you go the religious route, well, once again I don't want to spoil it for you but I smile just thinking about it.
Once you have conquered the planet (again), your civilization advances to the space age. As much fun as you may have had up to this point, brace yourself: the space stage is really where the full game begins.