A controversial video game that depicts a crusade of violence by Christians continues to soar in the bestseller charts this Christmas.

The game Left Behind: Eternal Forces is set in post-apocalyptic New York and features God's army battling the Antichrist. Based on the bestselling Christian fantasy Left Behind series created by Tim LaHaye and Jerry Jenkins, the game puts players in command of brainwashed legions fighting the "good fight" for Christianity.

"There is killing of course, it is a video game. But the basis of the game is spiritual welfare," said Troy Lyndon, CEO of Left Behind Games Inc.

"The antichrist is the main bad guy and so you are dealing with his henchmen. Both sides are trying to win the hearts and the minds of people who are not on either side," Lyndon, who describes himself as a "follower of Christ," told Reuters.

The game follows the success of the Left Behind books, which have sold more than 63 million copies worldwide.

The fantasy is an imagined scenario based on what might happen if the events depicted in the Book of Revelation, the last book of the Bible and the ultimate in theological end games, were to take place today.

Critics accuse its creators of mixing religion and violence to appeal to teenagers hooked on violent games like Grand Theft Auto.

A spokesperson for the Muslim Association of Britain called for the game to be banned, describing it as evil.

He said: "This game is irresponsible and highly racist. It demonises every other religion which isn't Christianity. People must boycott this violent game.

"It is a game that is prejudiced not just towards Muslims but every other religion which is not Christianity.

"Games like this poison the minds of young people and we urge people to boycott it."

Terry Sanderson, President of the National Secular Society, said: "Fundamentalists on both the Christian and the Muslim side are creating this kind of nasty, extreme propaganda and aiming it at young people.

"Parents need to be on their guard. I'm not into banning things or censoring them, but I think most Muslims and most Christians would recognise that this is crude and despicable hate-mongering and give it a wide berth. It is up to parents to ensure that their children are not exposed to this loathsome trash."

Many mainstream Christians and secular groups accuse some conservative evangelicals of displaying intolerance toward other faiths and beliefs - in this case through video games.

"We are trying to tell families that this game is faith-based violence and is not suitable for families," said Rev Timothy F. Simpson, a Presbyterian minister and the interim president of the Christian Alliance for Progress.

Lyndon, further defended the game saying: "The game is designed to be a classic battle between good and evil.

"We have deliberately censored the blood and it does not gratuitously depict death or violence.

"Left Behind is not taken from the Bible, it is a fictional story.

"In the initial missions, there is little emphasis on physical warfare and gamers are introduced to powers of influence which result in a battle for the hearts and minds of people."