Mana
Mana is spent to activate skills, and is shown on the bottom right of the screen as a blue orb. It recovers slowly over time, but can be refilled quickly with flasks.
Every class starts with 40 Mana, and gains +4 per level to reach 436 base mana at level 100. Every two points of Intelligence grants +1 mana. All classes have a base mana regeneration rate of 1.75% of their maximum mana per second, or equivalently 105% per minute.[1]
Additional mana and mana regeneration can be gained from high Intelligence, passive skills, modifiers on equipment, the aura Module Error: Too many skills found with q_where = skill.active_skill_name="Clarity". Please choose only one of the following ids:
ClarityRoyale - +(0-0.9) metres to radius, You and nearby Allies Regenerate (3-19.5) Mana per second (page)
Clarity - +(0-1.9) metres to radius, You and nearby Allies Regenerate (2.9-33) Mana per second (page), various unique items, and the Act 2 quest Deal with the Bandits in Normal. Clarity is important for high mana regen because it gives a flat "mana gained per second" bonus that is increased by all Mana Regeneration Rate +% modifiers.[2]
The when on Low Mana and when on Full Mana modifiers are not triggered with 0/0 mana.[3]
Passives
Many passive skill nodes grant additional mana or a combination of bonuses including mana, mana regeneration, reduced mana cost, reduced mana reserved on auras, mana leech, and mana gained on kill. Some passives will increase the amount of Mana regained from flasks.
The Blood Magic Keystone removes Mana, causing you to pay for skills with your life. Eldritch Battery converts all of your energy shield into extra mana.
Mana
In the case of Eldritch Battery, maximum mana is increased by an amount equal to total energy shield. In exchange, energy shield is reduced to 0.
Mana Regeneration
All classes have a base mana regeneration rate of 1.75% of their maximum mana per second, or equivalently 105% per minute.
Reduced Mana Cost
These passives reduce the mana cost of skills by a percentage. However, they do not reduce the amount of mana reserved by auras and skills like 
Tempest Shield, unlike the Module Error: No skills found with q_where = skill.active_skill_name="Reduced Mana" support gem.
Reduced Mana Reservation
For auras and skills like Tempest Shield, these passives reduce the amount of mana reserved by a percentage.
Mana Gain on Killing Blow
These passives restore a set amount of mana whenever your character kills an enemy. Unlike mana leech, mana gained this way is restored instantly.
Other
See also
References
- ↑ Malice (November 13, 2011; last updated October 7, 2013). "Mechanics Thread". Path of Exile Forum. Retrieved October 21, 2013.
- ↑ Mark_GGG (April 5, 2013). "auras and increased buff effect". Path of Exile Forum. Retrieved October 21, 2013.
- ↑ Daliel_GGG (August 13, 2014;). "New upcoming unique.". Path of Exile Forum. Retrieved August 13, 2014.