Tower defense (TD) games first started to appear in the early 2000’s as custom maps for real-time strategy games such as StarCraft and Warcraft III. The basic premise of a TD game is to protect a building or resource from wave after wave of progressively more powerful enemies, known as creeps. The player defends by building a variety of attack towers along the creep’s path, each with attack strengths and weaknesses.
Popular WarCraft III custom map X Tower Defense
Each wave of creeps will usually have different types of armour, weak only to certain attack types, necessitating the need for a well rounded tower build strategy. The creeps generally follow a set path, but certain TDs force the player to construct a maze of towers to slow the advance of the creeps.
As this unique custom map genre took hold among RTS gamers, the broader gaming world also began to notice. One of the first stand-alone PC Tower Defense games to appear was Master of Defence, released by indie developer Voodoo Dimention in 2005. The game is released under a shareware license for those interested.
Master of Defense
Despite the popularity of the genre, as of 2006, no one had yet bothered to develop a version on the ubiquitous Flash platform. David Scott, inspired by the WarCraft III Element TD, set out to create a Flash TD game, mainly to practice his development skills. In January 2007 Flash Element Tower Defense was unleashed. The game was a hit, and could be found embedded on over 12 000 Flash gaming websites by the time its creator got around to creating his own Flash gaming portal.
Flash Tower Defense
An acquaintance of Scott – Paul Preece – whom was inspired by his success, went on to develop the next big Flash TD hit, Desktop Tower Defense. Preece wanted to create a TD that required the player to maze their towers to block creep movement. The game was released in March 2007 and went on tothe become the flagship title of Scott and Preece’s new Flash gaming portal, Casual Collective.
Desktop Tower Defense went on to win the Gleemax Award for Strategic Gameplay (“The Gleemie”) at the 2008 Independent Games Festival. Numerous updates to the original have been made since, culminating in the current Pro version.
Over 2008 and 2009, the genre started to appear on numerous platforms. Handheld gaming devices received the likes of Ninja Town for the Nintendo DS, PixelJunk Monsters on the PSP, and the Apple App Store is littered with TD titles. Savage Moon arrived on the PS3. Xbox 360 and PC received the critically acclaimed Defense Grid: The Awakening. PC also lauded the arrival of Plants Vs. Zombies.
For those wanting to try out a few worthy free TD titles, below is a round-up of free titles:
GemCraft and its prequel clearly borrow from the popular WarCraft custom map Gem TD. The player combines different quality gems, each with unique attack qualities, to form powerful attack combinations. This is probably one of the most successful free Tower Defense flash games around at the moment.
StormWinds 1.5 and its sequel, The Lost Campaigns place players in a steampunk setting where they defend against various flying contraptions. Players are able to relocate their defense turrets and repair any damage done.
Momentum Missile Mayhem 2
Momentum Missile Mayhem 2 is a variation on TDs in that the player is responsible for firing their defensive weapons. The game also incorporates a physics system for the fired projectiles, which careen around the battlefield knocking out enemies.
Civilizations Wars is a TD and strategy game hybrid. The player will be responsible for manning defensive structures and for capturing offensive unit producing structures as well. There are numerous upgrade paths to explore making for quite an in-depth game.