Is playing electronic games that include ideas inconsistent with Islamic law considered a disbelief (kufr), and does it invalidate good deeds, and is selling these games forbidden?

Playing games merely for entertainment, while the heart denies and believes in the invalidity of anything in them that contradicts Islamic creed, does not expel one from the fold of Islam, but one incurs sin, because the heart's denial does not remove the sin. Prohibited games are not permissible to sell or play, for the Prophet, peace and blessings be upon him, said: "Indeed, when Allah forbids a thing, He forbids its price."