On planets whose native inhabitants have not yet developed space-faring technology, the Grox starships will still appear in order to abduct non-sapient creatures of the local fauna, possibly for study. Still, Grox starships are often found thousands of parsecs away from the core, where the Grox seem to attack other empires' colonies in an almost random fashion, only to destroy them and depart. They posses advanced technology and have colonies in 2400 star systems in the galactic core. The Grox are as evil as they are enigmatic.

The origins of the Grox are likely to be forever lost to history, but they are known to be one of the most ancient living empires in the Spore Galaxy. It is also possible that their biology is carbon-based but that they do not consider themselves as such because of their technological implants. The Grox may actually be silicon-based lifeforms. Strangely, the Grox also seem to be extremely toxic to other lifeforms, to the point that if a Grox citizen is abducted by an alien starship it will be automatically incinerated for being 'too toxic for your cargo hold.' Strong evidence that the Grox are not carbon-based lifeforms is given when they use the expression 'slow thinking carbon-based lifeforms' as an insult to other species. It is also possible that radiation is beneficial for their metabolism, since they will only colonize planets around the galactic core, an area known for the high radiation level caused by several black holes and densely clustered stars. Raising the T-score of a planet, which normally makes it habitable, will instantly kill the Grox. For one thing they are only able to survive on worlds classified as T0, which are usually barren lands with extreme temperatures and very thin atmospheres deemed uninhabitable for virtually all the other species. There are several evidences indicating that the Grox have a very unusual biology. Some speculate that the Grox are actually evolved versions of humans, since Earth in Spore is no longer inhabited by humans, and also because on the bottom of the Dance with the Devil badge (a badge earned by allying with the Grox, understandably a very difficult thing to do), you find the word good, but in atrocious writing. Their large eyes and ears are believed to provide them with acute senses, which was likely to have been their main way of preventing attacks before they evolved into an intelligent species. In spite of the fact that they lack any kind of claws or nails, and their only means of physical attack seems to be their teeth, their bite is also relatively weak compared to other carnivorous creatures.

Their feet sport two large toes and their hands are tridactyl. They are short-statured and have a carnivorous diet. Without their cyborg implants, the Grox are physically weak humanoids of mammalianoid evolutionary background.

Spore center of the galaxy