While most yet obtained achievements and their requirements are shaded but readable, there are nine which display only as "Secret" until achieved. Note that some games may still show a tenth dimmed "Secret" even though it is no longer obtainable.

Image Title Description
Can't Win For Losing image Can't Win For Losing Die at least once in every stage of Spore.
Pathological Cheater image Pathological Cheater Use a cheat more than 50 times.
General Custer image General Custer Lead 30 posse members to their death in the Creature Stage.
Cerberus image Cerberus Evolve a creature with three heads in the Creature Stage.
Slugger image Slugger Finish Creature Stage without using legs.
Medic image Medic Heal one of your tribe members back to full health 5x in a single game during the Tribal Stage.
Conclusion image Conclusion Finish the Civilization stage by launching ICBMS and destroying all other cities.
Fear of Flying image Fear of Flying Complete the Civilization stage without buying any air vehicles.
Oh the Humanity! image Oh the Humanity! Gained for destroying Earth using a Planet Buster in the Space Stage.