D.E.I. (Divide et Impera) is a game of exploration and survival set on Earth which has been devastated by a new ice age.

The cities of the future, from the crucible of civilization, have become icy deserts dotted with the carcasses of skyscrapers now reduced to uninhabited rubble. Between alleys of old London, bands of survivors use their abilities to explore and plunder the scarce resources that are left, to sell them to the Pure Caste in exchange for food and fuel. The only ones who still have high technology, the Pure Ones are the elected heirs of the old civilization. Protected by fortified citadels, they manage the bands of survivors, helping them in their research or putting them in competition, so that they cannot ally and threaten their domains.