Start by typing any letter to get the first country coloured. Type the name of this country: another one will get coloured, type its name... and so on, all the way!
Countries smaller than 20,000 km2 are not considered in this quiz so the smallest you have to watch out for is Slovenia
Would be better if the guessed countries would change to a different color. I couldn't even find what country was next after Djibouti. I thought no countries smaller than Slovenia were supposed to be included in the quiz??