While the tide pool phase introduces the player to the game and its editor, the creature phase plays a big part in terms of what the player's creatures will look like in the later phases. It is similar to the tide pool phase, but there are several important differences. The most obvious one is that it is a 3D environment. There will be other creatures inhabiting the world and most, if not all, of them will have been created by other players. If there is a lack of predators in the ecosystem and weak herbivores are everywhere, the game will automatically download a new species of predators that another player has created and load them into the current player's world to balance the ecosystem. The game will also download creatures in relation to how strong the player's creature is. If the player creates a bigger, tougher creature, the predators that are downloaded will likewise be stronger than average predators. Creatures' characteristics are categorized with a 5 star rating system in several areas: Speed, Stealth, Jump, Glide, Bite, "Spit", "Strike, "Sing", "Dance", "Charm", "Pose", "Health" and Charge. The creature also gains the ability to perform actions, such as "Call".
In this stage, the basic goal is the same: hunt food to earn DNA points, reproduce, and avoid being eaten by predators. The player must now locate a mate. Once the player's creature has laid an egg, they enter the creature editor, where they can evolve their creature by giving it better parts. When the egg hatches, the player becomes a baby version of the creature that spawned it. Aesthetically, this version of the creature will be smaller, with certain features exaggerated such as the head, and have a higher pitched voice. The baby will learn any new moves added via the editor and then instantly grow up. The ultimate goal of the creature phase is to increase the creature's brain capabilities slowly using DNA points. Once they have increased sufficiently, the player's creature becomes sapient and the player progresses to the tribal phase.
Swimming creatures were cut from the game, although creatures can glide great distances if they have wings.
The main units of currency are, as with the cellular phase, DNA points.
Egg
Finding a mate and creating an egg allows you to adapt your creature in the Cell and Creature stages of Spore. Click the Find Mate button on the bottom center of the screen and follow the sound waves. Doing this often will allow you to keep pace with the challenges you meet on your home planet. If you fail to Impress or conquer another nest, try changing some parts before you have another attempt.
Impress
Impressing other [[#nest|]]s and [[#tribe|]]s will eventually create an alliance. To do this, set your stance to Social and approach the target. A bar will appear above your target. To fill it, you must follow the instructions. If your creature or tribe is especially good at something, it is possible to make a mistake and still impress the target.
Nest
The Nest is where your creature heals and mates. Your young are born there. If you need to fill your [[#pack|]], this is a reliable place to do so. From time to time your nest may move just after you adapt your creature. Follow the trail on the mini-map and the black line on the terrain to find your new nest.
Pack
In Creature stage after growing a couple times, you are able to bring friendly creatures along with you in your pack. Their Social Skills and Combat Skills are added to your own. Other Creatures near their nests form packs of their own. Impressing a Pack larger than your own is difficult, while impressing a smaller pack is easier.