Are you in the mood to make some beasties?

Starting June 17, fans of “Spore” can start manufacturing their own digitized life forms when “Spore Creature Creator” debuts as a downloadable demo version and a $9.99 retail version. “Spore” itself arrives for PC, Mac and Nintendo DS in September.

In “Spore,” a massively single-player god game, gamers tinker with evolution by devising assorted living entities and guiding them toward civilization, with the ultimate goal of developing far enough to begin exploring space and meeting up with other strange creatures.

The full “Creature Creator” will contain all the beastie-making tools available in “Spore” and include tools to construct buildings, vehicles and aliens. The demo version offers just one quarter of the tools and will be made available at Spore.com and in a bundle with “The SimCity Box” on June 23.

“Spore” was created by the braintrust behind “SimCity” and was originally supposed to be called “SimEverything.”