A blue creature with eight legs, three eyes and a lobster-like claw is crawling out of the ocean. It coughs some water out of its lungs and then cries out for its friends to leave the ocean as well.

If the player of the computer game "Spore" then does everything right, the creature will continue to evolve, form a tribe, then a civilisation, and eventually leave the planet and explore the galaxy.

Spore is the brainchild of Will Wright, creator of the massively popular "Sim City" and "The Sims" simulated reality games, and was shown in a playable form for the first time at Leipzig's Games Convention this week.

After years in development, publisher Electronic Arts plans to ship it in the spring of 2008.

EA, which has sold a total of 85 million units of The Sims so far, has high hopes for Spore as well, calling it a breakthrough product of the kind that only hits the industry once in several years.

"We could not be more bullish about the potential for the franchise than we are right now," Chief Executive John Riccitiello told a conference call with financial analysts at the company's last quarterly results.

Spore is the latest in a genre of games such as "Age of Empires" where players plot strategy over a length of time. But Spore goes further and spans primordial and intergalactic eras.

The game starts with a "cell" phase, a simple organism floating in water that the player must help evolve -- modifying for example its extremities or mouth to make it survive more effectively.

In the "creature" phase, a player must find friends for their creation, and then enter the "tribal" phase.

EA only showed the "creature" and the "tribal" phase in Leipzig, but said the game was finished and playable from beginning to end.

The creatures a player encounters throughout the game, as well as the buildings and vehicles, are not a fixed set -- the world is populated with the creatures created by other players that are in a similar stage of evolution and shared online.

The game also adapts to playing styles.

"Throughout Spore you have the choice of being friendly and social, or being aggressive and killing everything," said Darren Montgomery, part of the Spore team who was presenting the game at the Leipzig fair.

A player can bring gifts to a neighbouring tribe in the hopes of recruiting them to join his -- or burn down their hut to make them surrender.

"How you play in one phase will affect how it unfolds in the next one. If you continue to play aggressively, other creatures will be aggressive and your civilisation will eventually be military," Montgomery said.

But even friendly creatures must survive. Hunting for food, a group of creatures that resembled blue lizards with big eyes walking on two legs used clubs to kill other creatures and then cut them up for food, a jarring contrast to the game's friendly, cartoon-style design.