Pretty simple achievement. You can also do this while going for Hearts and Minds. In ONE game of Explorer, Hot Seat mode with four players, you will need to capture a territory, not just own a territory (as in ones already marked that you start the game off with). Make your way around the 6 continents, capturing at least 2-3 territories. Again, you will want to avoid territories with 250 & 500 points as mush as possible. Now, have the second player capture 2 territories adjacent to each other and just hop back and forth in that continent, that way the second players turn will be forfeited.