Unlike in other tower defense games, turrets can be placed anywhere and the enemies will go around them, forcing them to walk along any path the player makes. It is not possible to block the path however. Fieldrunners offers three types of gameplay: Classic, Extended and Endless. Playing in Classic and Extended modes limits the number of rounds in which the player must defend to 100. Classic only lets players build the original four towers, Gatling, Goo, Missile, and Tesla. Extended mode adds the two new towers, Flame Tower and Mortar Tower. In Endless mode, the player may defend indefinitely. In any mode, the player may play in Easy, Medium, or Hard mode.
Maps
Maps were released over a course of updates. Only Grasslands was present during the initial release, featuring an open field in which enemies enter from the left and exit to the right. Crossroads was later released, also featuring an open field but enemies cross from top to bottom in addition from left to right. Drylands later followed, featuring an open field with three entry points, two from left to right and one from top to bottom. Two maps were included as in-app purchases, Skyway and Frostbite. Skyway features a field containing obstacles and with one leftmost entrance. Frostbite has four entrances on each side of the map which all converge in the center. Another update introduced a free map, Crystal Caves, and two in-app purchase maps, MudSlide, and LavaFlow. Crystal Caves features an open field with one entrance encircled by an additional train route. Mudslide features a field containing obstacles, a left entrance and an intersecting train route. Lavaflow features a field with two intersecting train routes and one left entrance.
Reception
Fieldrunners has received generally positive reviews, with the PSP version scoring 81% at the review aggregate website Metacritic. IGN gave the game an eight out of ten rating, and highly recommended it. was highly critical of the PC port, however expressed enjoyment of the mobile releases. Of the iPhone version, Stuart Dredge of Pocket Gamer noted its "clever controls and cartoony visuals", calling it "the best Tower Defense game on iPhone so far". The PSP version of Fieldrunners scored a high 81/100 on Metacritic. Reviews for the iPadFieldrunners HD version have been positive. However, ratings on the game have been relatively lower than other games due to the fact it is a paid game that has IAP for the full game and the high crash rate for some players. https://itunes.apple.com/us/app/fieldrunners/id292421271?mt=8