Fire is first introduced in Virtual Villagers 2: The Lost Children as a puzzle. It serves as a technological advantage as long as it can be kept running.
In Virtual Villagers 3: The Secret City, the fire plays a less significant role in the game. One of the puzzles, Weather Dancing, requires the Tribal Chief and three Adept Farmers to be dragged over the fire so they can learn how to control the weather.
Fire also returns in Virtual Villagers 4: The Tree of Life. It plays a role in the first puzzle, The Cutting Tools. Fire is also used in another puzzle, where you must dig out the rubble, heat up four rocks in the fire, and place them there. Then, you will apply leaves on top. Once that's finished, you've unlocked the second food source, where you shake down fruit, cook it on the rocks, then take it to the food bin.