Everyone is going to get sick if you don’t do a good job setting up your tower defenses in the Sewer Germ Tower Defense free online flash game. There are some nasty germs swimming in the gross sewers and they are going to spread their diseases if you don’t kill them with your tower defense skills. You have a bunch of different towers and turrets to place along your map. Each tower or turret has different shooting and firing powers so use your best tower defense strategy to place them in the best spots to stop the germs from escaping. Best Sewer Germ Tower Defense games.