Computer gamers who like a challenge can now take on one of the toughest around: saving the entire planet, this time from climate change.
Billed as a strategy game with a social conscience, "Fate of the World" sees players try to protect the world's climate and resources while managing a growing population demanding more power, food and living space.
"'Fate of the World' is a scenario-based game where you run Earth for 200 years and you save it or potentially destroy it. The whole power is in your hands," said the game's British inventor Gobion Rowlands.
The player takes charge as head of the fictional Global Environment Organisation (GEO). They can impose policies such as banning logging in the Amazon rainforest, making all Europe's public transport run on electricity or slapping a one-child policy on the whole of Asia.
However, such power comes with grave consequences.
If, for example, you decide to bring down the birth rate to protect natural resources, the workforce could plunge and people could be forced to work until 80, triggering unrest against the GEO.
Gamers see the impact of their decisions: orangutans are saved from extinction, global temperatures drop by a degree; however, bad moves could see Europe battered by floods, or Africa ravaged by war.
"Even if they choose to destroy the world, they still learn more about the subject," said Rowlands, the 35-year-old head of video games developer Red Redemption, which employs 15 people at its base in Oxford, southern England.
The game was based on scientific, economic and demographic data from sources such as NASA, the United Nations and Oxford University.
"Fate of the World" was developed in partnership with academics working under Oxford University climate change expert Doctor Myles Allen.
The game "allows people to experience the decisions we are likely to confront and makes clear there are no easy answers", Allen said.
"Fate of the World" is a sequel to Red Redemption's 2007 "Climate Challenge" game produced by the BBC, which focused only on Europe.
Despite its straightforward graphics, the game has been welcomed by environmental and development groups, which were on board throughout the process.
"This game offers a new way of telling the climate change story and helps us to reach new audiences," said Ged Barker, the British digital campaigns leader for the Oxfam aid agency.
"Those who play the game will learn about climate change... without having to read lots of material that they might find boring."
The collaboration between Red Redemption, which is on its fifth computer game, and non-governmental organisations could go further. Rowlands is trying to negotiate a deal whereby a share of the profits go to their coffers.
A taster version is available to download now. The full version will cost 20 pounds when it is released in February.
The French, Spanish and German versions come out in March.