The latest Anno trailer highlights the difference between the city-building sim's two factions. There's the Ecos, who use sustainable energy sources, floating blimps that clean the air and a smug sense of satisfaction to power their economy. The Tycoons plough through Anno's luscious terrain with complete disregard for the eco-balance. Their cities are sprawling masses of rust and fumes. They can store the negative products from their enormous factories inside mountains, which is the equivalent of sweeping all your rubbish under a sofa in the vain hope it will one day turn into gold. This never works.