Some Heroes and units have Auras. These Auras will affect friendly units around the Hero. You can find out if an Aura is active on nearby units by selecting them and viewing the information screen which will show the spells affecting them. Not every Hero has an Aura. If you use the same Aura from two Heroes they do not stack, but since the Auras pulse on and off, the units affected will be covered by the Aura more often. Heroes with Auras benefit from their own Aura. Auras are Universal spells. Universal spells, unlike Magical spells, can work against anything. Magic-immune units like Dryads, are affected by Auras from friendly units only. Dryads will receive the Trueshot Aura from a friendly Priestess of the Moon and be unaffected by Thorns Aura from an enemy Keeper of the Grove. Auras will not be active if the unit is Hidden (Shadowmeld) or Invisible. SpellcastersEach race has 2 dedicated spellcasters. They all start with 200 Mana and gain a total of 400 Mana with Adept and Master Training. Spellcasters are typically weak and need protection. Humans: Priest, SorceressOrcs: Shaman, Witch Doctor, Spirit Walker (different stats)Night Elves: Druid of the Claw, Druid of the TalonUndead: Necromancer, Banshee It’s best to build two Spellcaster buildings (such as two Arcane Sanctums) so that you can both train new units and research upgrades at the same time. This also allows you to train two different types of spellcasters at once or to train several identical units more quickly. For example, with two buildings you can build a Sorceress and a Priest at the same time. The Night Elf Druids both have another animal form which changes them into different types of units. Anti-SpellcastersAnti-Spellcasters are, of course, designed to fight spellcasters. Humans: Spell Breaker Orcs: Spirit WalkerNight Elves: Dryad, Faerie DragonUndead: Destroyer The Dryad is sort of a hybrid unit since it is both a spellcaster and a combat unit. Dark Ranger: SilenceThe Dark Ranger’s Silence ability can be used to prevent spellcasters from casting spells. Spell ResearchSpellcasters must research Adept Training and Master Training before they receive all of their spells. These training upgrades give the spellcasters a total of 200 extra Mana and increase their Mana regeneration rate. These upgrades are worth getting because of the extra Mana and Mana regeneration. For example, Priests receives Healing without training, but the additional training will allow them to Heal more often. Researching Master-level spells (Bloodlust, Inner Fire, etc.) requires a 3rd-level Town Hall (castle, Fortress, etc.). Line damage spellsLine damage spells such as Shockwave and Carrion Swarm do not damage a targeted friendly unit. Ultimate SpellsEach Hero has one Ultimate Spell — his most powerful. To use this spell a Hero must be at level 6 or higher. Channeling ultimates cancels invulnerability. If an invulnerability spell is used while channeling, channeling will end. EtherealEthereal means: “characterized by lightness and insubstantiality; intangible.” Units that are Ethereal can only be damaged by units that have the attack type “magic” such as spellcasters. Ethereal units cannot attack but can cast spells. Ethereal units take 66% bonus damage from spells and magic damage type. Units healed while Ethereal gain an additional 66% benefit. For example, casting level 1 Holy Light on an Ethereal unit for 200 hit points actually ends up healing 333 hit points. Only “spell” healing is affected by this; item healing and aura healing are not. Spell ImmunitySome Creeps and units such as Golems, Dryads, Infernals, and more are Immune to magic. Spell Immune units cannot receive positive buffs such as Roar, Bloodlust, or Inner Fire nor receive negative de-buffs such as Curse or Slow. They will receive Auras since auras are non magical. They also cannot be damaged by units who have the “magic damage” attack type. Spell Immune units can be hit by certain abilities. Resistant SkinReduces the duration of negative spells and renders the unit immu