E3 2005 is under way and we made absolutely sure we took the opportunity to visit with Maxis' Will Wright to get an up-close demonstration of Spore, an all-new game that will let you evolve from the petri dish to interstellar travel. As we saw, you'll begin your life as a microscopic organism swimming around in a primordial soup, devouring any microbes smaller than you and avoiding any that are larger that might potentially attack you. Once you devour enough of your fellow microbes, you'll actually be able to evolve by using a universal editing screen. At the microscopic level, you may be able to add cilia (tiny flapping "hairs" that let you move more quickly), flagella (whiplike projections that also help you move quicky), as well as defense mechanisms that will let you fight off larger beings.

Eventually, you'll evolve into a multicellular being. Wright's sample creature resembled a three-eyed, three-legged alligator that swam lazily about under the sea after about 10 generations removed from the microbe form. Like in the primordial soup, in this form, you'll be able to devour smaller beings and fend off (or flee from) larger ones. Once you earn enough "points" by doing things like eating enough to survive (you can choose to be either a carnivore or herbivore), you'll be able to lay an egg that will let you design the next generation of your creature. If you remove your creature's fins and replace them with legs, your creature will sink to the bottom of the ocean, then simply walk onto land to begin the next phase of its life.

On land, you'll wander across the surface of an earthlike planet populated by creatures actually created by other players. Spore won't be a massively multiplayer game, but each time you or any other player designs a creature, then that creature will be uploaded to a master online server that will automatically populate your worlds with any player-created creatures that are applicable to the needs of the world. Wright explains that the game will model a functional ecosystem with a "food web"--so if you create a world that needs a flying carnivore creature to complete itself, the Spore master server will search its own database for a player-created flying meat eater and download it to your world, which, as Wright puts it, will "bring together the best aspects of massively multiplayer games without the restrictions."

Wright demonstrated how you'll be able to teach your creatures new behaviors by combining existing ones (for instance, using the "eat" function while commanding your creature to move will teach it to drag its prey along the ground). Different creatures will have different strengths and weaknesses, but as Wright explains, "there will be no single best creature." Larger and stronger carnivores will also be slower and may have trouble catching their prey, for instance. At this stage, you'll want to evolve by laying an egg, but you'll need to put out a mating call (our creature emitted a quailing cry and a visible ring of white rings around itself) until it found another creature of its species. Once it found a prospective mate, the two creatures got together to the tune of a Marvin Gaye-esque R&B song, and eventually laid the egg. Once you've earned enough points to lay an egg, you'll be able to edit your creature once again, adding weaponlike additions to its body (such as a tail stinger), additional legs, and spending points on your creature's brainpower.

With enough points spent on developing your critter's brain, you'll eventually see your creatures band together as a primitive tribe. In the demonstration we watched, the three-legged alligators had already gathered a small pile of fruit and vegetables outside of their primitive huts. At this stage, you'll assume control of that particular tribe (and may find yourself in competition with other tribes of the same race). Surviving and thriving in the world will let you purchase upgrades for your tribe, such as warlike enhancements, like a rack of spears. This sort of addition may make your tribe more proficient in the art of war, but may also make them a characteristically more-aggressive race. We watched as Wright dropped a pair of bongo drums next to the spear rack, causing two of the critters to begin pounding on the drums with their tails while four others wrapped spears in their tails and danced around the campfire.

Over time, you'll be able to advance your civilization by purchasing upgrades for your primary town's hut, eventually building out a full-on city. The city we saw was a whimsical-looking town full of Baroque, pastel-yellow buildings. At this point, you'll be managing your funds and citizens' happiness, as well as looking outward to dealing with other tribes. Wright drew a comparison to the classic Firaxis strategy series Civilization, in that you'll be able to grow your holdings either through military force, economic force, or impressive culture that will let you assimilate other tribes. We watched as a rival tribe, which had apparently focused on technology and had a stark, metallic city of skyscrapers (as opposed to our tribes' Dr. Seuss-like buildings), sent out a small group of tanks that rolled across the hills and opened fire on our walls. We responded by researching a squadron of fighter jets to dive-bomb our enemies. But Wright demonstrated an even more important priority for civilizations in Spore: the space race.

The top-level terrestrial tech you can research will be the UFO--a gigantic flying saucer that will let you cruise around the face of your home planet and collect environmental objects and plant life from around the globe, as well as abduct any life-forms you'd like to transport elsewhere. By zooming out far enough, we were able to see our UFO in the solar system and we could see it actually traveling to a different planet. Different planets will have different climates and may not have livable atmospheres, so dropping a creature onto a nearby moon without any colonization will be a good way to watch a creature explode. In order to colonize planets, you'll need to launch hydrocarbon canisters that will eventually create a breathable atmosphere. If you create colonies early, you'll have to enclose your cities in gigantic glass bubbles of air (but as Wright pointed out, you might just as well make a race of superintelligent dolphins that live below the sea whose space colonies would instead be filled with water).

By zooming out even farther, you'll be able to see the entire galaxy and actually travel to other star systems created by other players. From this view, you'll be able to play as an intergalactic conqueror, but you could just as soon attempt to make friendly contact with other galaxies. Doing so may let you take on missions for other races. Wright compared this style of gameplay to Grand Theft Auto's free-roaming gameplay.

Spore looks incredibly intriguing and it seems to make the highly complex dynamics of evolution seem highly intuitive, and even simple. Since the game procedurally calculates everything, you won't have to manually edit any of your creatures or buildings (though you can if you wish to), and you'll be able to watch your civilization grow from a single microbe. The game is scheduled for release in fall of next year. Stay tuned to GameSpot for more updates.