Defenses are a core mechanic that, when placed, target and deal damage to enemies. Defenses have a level, associated mana cost, as well as a number of defense units required to place a defense down. Defenses have specific properties that pertain only to that defense (ie. range, or reset time - as two examples). Each hero has 5 unique defenses (barring the Rogue, who uses special abilities in the place of defenses). Some defenses have a Targeting Priority, and some defenses are influenced by hero abilities. Please view the corresponding hero's defense page for more specific details about a given defense.
Tips
Ctrl+Mouse wheel scales aura/trap sizes and rotates towers.
Below are some links to each of the heroes defenses, choose wisely defender!