Mana is the recurring second player resource, which, unlike Life, reflects the amount of energy that a character has. It is used for casting spells or applying abilities, draining mana with every cast, more powerful spells consuming more mana.
If mana is too low, casting the costly spells will be temporarily disabled, until the character has generated enough mana again. Mana bar sphere is depicted as a glass orb filled with bright blue glowing liquid in all three games.
The amount of maximum mana is affected by items with mana or Energy (Magic in Diablo I) attributes. In Diablo I, mana does not recover over time, so the player will need to find a Mana potion to refill it. In Hellfire, one may speak to Adria to gain full Mana. In Diablo II, mana slowly regenerates by itself (Warmth skill, for example, may enhance its recovery greatly), and some Shrines are either replenishing player's Mana or increasing its regeneration for a short time.
Mana cost of a spell or skill may (but is not guaranteed to) change with spell or skill level. Generally, in D1, it can drop up to 50% of base value (with some exceptions). In D2, it can (with enough points) go to zero, making a skill free to use. Most spells and skills, however, consume more Mana as they grow more powerful.
"Witch doctors’ inborn connection to the Unformed Land allows them to tap into a deep well of spiritual energy, called Mana. Mana is a vast but slowly-regenerating resource; witch doctors must be choosy with their attack spells and hexes to ensure that they don’t leave themselves depleted of power and exposed to enemy attacks. Since Mana returns ponderously, witch doctors conserve it by relying on semi-permanent additions to their arsenal, such as their summoned mongrels and the horrific gargantuan, which can offer protection and chew through enemies without any further mana cost. Witch doctors have a sizeable reservoir of energy to call upon at once, and, when they need to, they can deploy immense blasts of destructive force and cut a swath across nearly any battleground in a short period of time."— Game Guide(src)
In Diablo III, only Witch Doctors have Mana due to balancing reasons. In exchange, the classes have alternative resources that have different ways of regenerating (for example, the Monk has Spirit, which generates points for every Primary attack he lands).
A Witch Doctor's inborn connection to the Unformed Land allows them to tap into a deep well of spiritual energy, called Mana. A Witch Doctor may have up to +450 Mana from items (+600 with legendary items), and +42 Mana regeneration (+7 more from Kormac). Spiritual Attunement grants 10% maximum Mana and 1% Mana regenerated per second, while other active and passive skills may recover Mana on kill (or from health globes), change Mana costs (from -10% to +30%), recover it when activated, refund Mana when cast, or increase effective Mana regeneration (up to 30%). Mordullu's Promise makes Firebomb generate additional 100-125 Mana when cast. Paragon levels may grant +200 more Mana. Rush of Essence is unique in that it causes each Spirit spell cast to restore a fixed amount of Mana, regardless of its cost, effectively making these spells free to cast.
Since Mana recovery rate is low relative to other resources, Witch Doctors may easily run out of it in battle. However, they may choose to discharge all their most powerful spells at once and pray that would be enough. The alternate way is to rely on pets, which do not have Mana cost.
|Diablo I||Diablo II||Diablo III|
|Strength — Damage |
Dexterity — Attack Rating • Armor Class • Block
Vitality — Life
Magic — Mana
|Strength — Damage |
Dexterity — Attack Rating • Defense • Block
Vitality — Life • Stamina
Energy — Mana • Mana Regeneration
|Strength — Damage • Armor|
Dexterity — Damage • Armor
Vitality — Life
Intelligence — Damage • Resistances