The Galactic Core

In the space stage, when you are opened up into a huge veiw of the galaxy, reaching the galactic core is your main objective. It is said that the grox home planet is at the very center of the galaxy. When you reach the galactic core, you are met by a cutscene, followed by the game credits. The final cutscene of spore is the only cutscene to have full english voice acting, aside to the usual nonsense alien blabber.

In Reality
In reality, the galactic core is a super massive black hole that sucks anything (including light) into it.