The fate of the human race is in your hands in a forthcoming game by the British games guru Peter Molyneux.
The game BC is set in a prehistoric age millions of years ago, with a player in charge of a handful of vulnerable human beings.
Go back to a time when life was short, nasty and brutish
"The story is about the survival of the human race," Mr Molyneux told BBC News Online, "in a gory, brutal and savage world."
BC takes the genre of simulated worlds where a player control everything that happens and transfers it to a land that time forgot.
Mr Molyneux is best known for creating this genre of god games. One of his best known, Black and White, has sold close to two million copies.
Life and death
Games that allow players to manage cities, theme parks or even people have been major successes.
The best-selling Sims computer game, in which players create neighbourhoods of simulated people and control their lives, has made millions for the company behind it, Electronic Arts.
In The Sims, characters need to deal with mundane tasks such as paying bills or going to the supermarket.
In BC, even mundane tasks like collecting firewood can be a matter of life, with vicious velociraptors roaming the Earth.
Mr Molyneux said he and his colleagues come up with the idea for the game over a few drinks in the pub.
"We thought, if you could go back to prehistoric times, how could you change the world?" he said.
In BC, a player has to lead a human tribe over the course of 50 years. Your task is to teach them skills to survive in a world full of danger, not least from a rival race of ape-men.
In the game, explained Mr Molyneux, gamers will have to learn to use the environment to survive.
So a piece of flint can be turned into an axe. Or boulders could be rolled to kill prey.
Your tribe will learn from your actions
"Your tribe will learn from your actions," said Mr Molyneux. "You can teach them to build houses or bridges."
He said players could learn important lessons about how their actions affect the world around them.
In the game, if a player decimates the land by chopping down the trees for firewood, dinosaurs will move away, leaving your tribe living in a virtual wasteland.
BC is being developed by Intrepid Computer Entertainment in association with Peter Molyneux's Lionhead Studios and is due to be released for the Xbox in March 2004.