Mana

Mana (also known as MP, which is short for mana points) represents the magic power of a unit. It is used as a cost for majority of active abilities. Every hero has a base mana pool of 0, while most non-heroes only have a set mana pool if they have abilities which require mana, with a very few exceptions. The mana values are set and can't be altered. This means a unit's maximum mana pool can never drop below its set value. However, a hero's mana pool gets bigger for every intelligence point they have. Each point of intelligence increases a hero's mana pool by 13. Since every has some base intelligence and gain intelligence as they level up, their mana pool gets bigger the higher their level is. A hero's intelligence cannot drop below 1, so the minimum possible mana pool a hero can have is 13.

Note: Although gaining/losing intelligence usually does not increase a hero's current mana, some abilities which grant/reduce intelligence are coded so that they also increase/reduce current mana by 13, instead of only maximum mana.

Display
The mana of a unit is displayed in the hud. For some units, it also may be displayed in the game world.

Hud mana bar
Mana of the selected unit is displayed in the HUD as a blue bar at the bottom of the screen. Unlike the health bar, the mana bar has always the same color. The left number at the center of the bar is the unit's current mana points and the right number is its maximum mana pool. Though not displayed in the hud, a unit's total mana does use decimal numbers. The visible numbers in the hud are always rounded up.

The mana regeneration value is only visible on the hero and creep-hero mana bars in the HUD. The regen from other units is not visible. Though the hud shows only one decimal for mana regeneration, it uses more decimals. The value in the hud is rounded up.

Over-head mana bar
The mana bar of heroes and creep-heroes are displayed right above their heads, below their health bar. Just like the mana bar in the hud, this bar is always blue. Even when a creep-hero has no mana pool, a mana bar is still drawn below their health bar above them.

There are no different type of mana bars. They do not have lines like the health bars and do not differ from each other in any way.

Modifying mana
Some heroes, units (neutral creeps and summoned units) and items have abilities that can affect the mana pool of a, or multiple units.

Current mana increasing abilities
Just like healing health, a unit's current mana can be increased by many abilities, mostly refered as restoring mana. Restoring mana cannot increase the unit's mana beyond its maximum mana pool. Spells may restore mana in a burst on a target, restoring an amount of mana in an instance, or restore mana over time, where the amount is split up in multiple instances. The difference between restoring mana and regenerating mana is that restoring is independent from the regeneration ticks. Unlike regeneration, the restore intervals can vary. Restoring mana is not reflected in the regeneration number on the mana bar.

The following abilities are able to increase unit's current mana:

Current mana reducing abilities
There are many abilities capable of reducing, or more commonly refered as burning if it also causes damage, and draining if otherwise, a unit's current mana pool.

The following abilities reduce a unit's current mana:

Maximum mana affecting abilities
Besides intelligence and raw bonuses from items, there are only very few abilities which can increase a unit's maximum mana.

Mana granting items
Many items grant their owners a mana bonus, increasing their maximum mana when equipped, either by increasing their intelligence, or by just giving them a flat bonus. In either case, the current mana percentage stays the same.

The following items increase a unit's maximum mana pool. The affects are limited to the item's owner, which must have the item equipped. (items in grey fields grant mana exclusively through intelligence gain)

Basic items

Upgraded items

Mana regeneration
Mana Regeneration determines the amount of mana a unit regains each second. It is shown as a small number with a + sign at the right side of the unit's mana bar.

Heroes regain mana in 0.01 second intervals. Each second, a hero regains mana equal to their base rate (0.01 for every hero, except with 0.02), plus 0.04/second for every point of  intelligence, plus any bonuses from items and abilities. There are sources of flat mana regen bonuses and sources of mana regen sources which increase mana regeneration by a percentage. The Fountains of both teams regenerate any unit belonging to their team within a 800 radius by 14 base + 4% of the unit's maximum mana per second. Mana regeneration is not capped, however the HUD won't show any mana Regeneration over 500 mana per second.

Any source of flat mana regeneration simply adds its value ontop of the unit's mana regeneration, if it has a base mana regen. This flat bonus is unaffected by any percentage mana regen bonus.

Percentage mana regen multiplies the unit's base mana regen + regen from intelligence and then adds it to its mana regeneration. This means that this bonus is also unaffected by other percentage mana regen sources.

Example:


 * A hero with 20 intelligence has a main mana regeneration of (0.01 + 20 * 0.04) = 0.81.


 * One increases it to: 0.81 * (1 + 50%) = 1.215 MP/s
 * Two s increase it to: 0.81 * (1 + 50% + 50%) = 1.62 MP/s
 * Using a ontop of that results in: 0.81 * (1 + 50% + 50%) + 3.75 = 5.37 MP/s

So the full formula is

(Base mana regeneration + 0.04 * intelligence) * (1 + sum of all percentage bonuses) + sum of all flat bonuses

Without regeneration bonuses, the time to regenerate all mana typically ranges from 318 to 324 seconds.

Base mana regeneration
Heroes

Every hero has a base mana regeneration rate of 0.01 MP/sec, except for with 0.02 MP/sec.

Creeps

All units without a mana pool also have no mana regeneration. All other units have the following base mana regen:

Summons

All summons without a mana pool also have no mana regeneration. All other summons have the following mana regen:

Modifying mana regeneration
Just like for mana, there are many abilities and items which can change how fast a unit regenerates mana. Most of them increase mana regeneration rate by adding a flat bonus or by a percentage, but some also increase it based on certain things, like health or attributes.

Mana regeneration affecting abilities
Mana regeneration affecting abilities usually either affect the regen rate heavily, but only last temporarily, or affect it in smaller amounts, but may last permanently.

The following abilities affect a unit's mana regeneration:

Mana regeneration granting items
These items passively increase the owner's mana regeneration by merely having them equipped. They either grant a flat bonus, or a percentage bonus.

Items in grey fields grant mana regeneration exclusively through the intelligence they grant.

Basic items

Upgraded items