The most popular mod for spore, BetterSpore expands the core Spore game to make it a more fun experience!
BetterSpore is one of the few mods for Spore out there that is really worth getting. It adds many features that should of been included from the get-go, as well as many new parts for creature creation. It adds many hours worth playing to Spore. Although there is no easy way to uninstall it, it is still worth getting.