At each of Spore's five stages, from the microbiotic to the intergalactic, there is an eternal choice: kill or... don't. When you start, as a microbe with teeth, it's kill or be vegetarian. When you evolve enough to crawl from the primordial soup to dry land, it's kill or sing little songs to befriend things.
Once your species forms a society and decides what buildings to have in its first village, it's kill or bring plates of oranges to appease semi-sentient tangles of legs and mouths. At the civilisation level, it's build killing-machines or maraca-factories. Maracas, of course, help when you're doing a little dance to befriend a bristling heap of fanged mouths.