All in all a great game that has been in the family all infested with us from the youngest (8 years), up to my husband, who, however, still has to give its comments only to create creatures or buildings.
The only drawback, you should always save often times during the game, because, unfortunately, tends "Spore" to like to crash, which is very annoying when you finish missions and forget has to save. On the computers is not, which are up to date;)
Of course you can criticize that for not very extensive supplement the price but somewhat overpriced. But would then certainly in all areas can be an extension, for example, also new components for buildings and vehicles.
So you bite into the sour apple halt, and it can use all creatures.
Conclusion: Expansion is recommended if one wants to build still more different creatures and not only "core Spore" games and utilize creatures. One should allerdinsg save the money you put on the build and tinker from creatures not as the increased value. To this end, the selection of the main game is enough.
