Procedural generation

The earliest computer games were severely limited by memory constraints, forcing things like levels to be generated algorithmically, proceduarly, on the fly: there simply wasn't enough space to store premade levels and artwork. Today, most games include (measuring by memory space) thousands of times as much data as algorthmic mechanics. For example, all of the buildings in the large gameworld of Grand Theft Auto were individually designed and placed by artists.

Because the Spore gameworld is procedurally generated, it can be as large, varied, and detailed as it needs to be without an expensive team designing each element individually. Because of this malleability, users' creatures will react realistically to a wide range of customizations.

In Wright's first public demostration of Spore, he created a tripod creature in the creature evolution editor. The game then figured out how a lizard with three legs and a prehensile tail should walk. Wright then showed several more pre-made creatures which moved realistically, despite their exotic design.