The Tower Stack Glitch allows players to place several of the same tower on one spot (i.e. stack). It can be used to summon where the hero is standing or summon from any distance, even offscreen.
Though likely unintended by Dungeon Defender's original developers, tower stacking has become an invaluable tool to save DU protecting attack towers with barriers and blockades, especially on many of the CDT maps.
Tower stacking works by pressing the corresponding hotkey and Left Clicking or Spacebar (keyboard and mouse), or A or X (on a controller) almost simultaneously after placing the first tower in a stack. Since this requires nearly frame-perfect timing, a macro is often used to automatically press Spacebar or A/X the moment the tower's corresponding hotkey is pressed.
Depending on how the builder goes about it, he/she may not be allowed to move their mouse or either control stick, except when setting rotation or length.
Stacking minions is done with one of two different methods, both of which the Summoner must be in Overlord Mode. Minions ignore collision with all other minions for the first few seconds after they're summoned, allowing them to be stacked. Alternatively, the Summoner can keep their mouse/control stick completely still to summon any number of minions at one location their stocked mana and unspent MU allows.
- Tower stacking only works on PC and console.
- Unless moved by a Jester with a low Tower Range stat, Huntress/Ranger traps and Monk/Initiate auras of the same type cannot overlap where they're placed. Series EV's beams can be stacked one end at a time; both ends can't overlap.
- Use the + and - keys to cycle between the Towers when you want to upgrade them to specific levels.