Editing Damage (section)

==== Magic shields - variable R<sub>4</sub> ====
There are many spells that modify damage, but most do so by increasing or decreasing the attack and defense skills of allied or enemy troops. [[Stone Skin]], for example, increases an allied unit's defense skill, and therefore modifies damage by affecting variable R<sub>1</sub>. The only spells that modify damage directly are [[Shield]], [[Air Shield]], and [[Forgetfulness]]. Shield reduces all [[melee]] damage done to the hero's troops by 15% (R<small>4</small> = 0.15), or even by 30% when cast with advanced or expert proficiency. [[Air shield]] reduces all [[ranged attack|ranged]] damage done to the hero's troops by 25% (R<small>4</small> = 0.25), or by 50% when cast with advanced or expert proficiency. Similarly to Armorer and arrow towers, also Air Shield actually increases the damage from arrow towers instead of decreasing it.