field runners

Create a maze type path using towers as your walls to give the fieldrunners a long walk to your gates.Gatling Towers are the cheapest and weakest, not powerful enough to do much damage past the first 20 rounds. Use them mainly as walls of your maze.Build Missile Towers early, and try to place along the line between gates. They are invaluable to stopping the airborne fieldfunners (if player on Medium or Hard, Lightning Towers will be more useful.)Place a tower or two at each of your gates early on to finish off any fieldrunners that make it past your main towers.Lightning Towers are very costly but very powerful, and become absolutely necessary as the fieldrunners get tougher, or to defeat the power units like Blips and Tanks. Some of the more advanced strategies use Lightning Towers instead of Missile Towers. Make sure you have Goo Towers set up every few spaces along your maze to keep fieldrunners constantly goo'd throughout their journey.The higher level the Goo Tower, the slower the goo'd fieldrunner will move.