User:Zootsko/Drafts/Formulas:Mana Regen

The condition of a game character gaining mana points over time is referred to as mana regeneration. There are several sources of mana regeneration, each with their own characteristics.

Spirit-based regeneration
All characters with mana points passively regenerate some mana in ticks of 2 seconds. The amount of mana gained per tick is based on the character's class and spirit attribute, according to the following formulas:

From these formulas it follows that increasing a character's spirit yields constant returns for mana regenerated per tick.

Five Second Rule
When a character completes casting a spell which cost mana, the effective amount of mana gained per tick from spirit-based regeneration becomes a ratio of the normal listed above, for a period of 5 seconds. During this period mana regeneration is said to be interrupted. This is commonly referred to as the 'five second rule'.

By default, your interrupted mana regeneration ratio is 0%, meaning that spirit-based mana regeneration is suspended for 5 seconds after casting. Several effects can increase this ratio, including:

* Depending on rank

Note that spells which doesn't cost mana, will not start the 5 second timer and will let you continue regenerating mana. Nature's Swiftness costs no mana, and will not invoke the five second rule. Spells casted with the Clearcasting state also will not start the 5 second timer. Totems, on the other hand, will start the 5 second timer.

Prior to the 1.4.0 patch, you also did not regenerate mana during the casting of the spell. In-game textual references to the five second rule still read "while casting" where they actually should read "after casting".

Direct regeneration
Many effects increase mana regeneration directly i.e. without increasing spirit. These effects are governed by different rules than spirit-based regeneration.

Mod Power Regen effects
Most items which restore mana, including various types of water as well as equipable items such as Anathema, works similarly to spirit-based regeneration in that they regenerate mana in ticks of 2 seconds. Unlike the spirit-based regeneration, however, the five second rule does not apply to these effects. That is, after casting a spell, mana regeneration from these items will continue. This can make a difference in fights, where long chains of uninterupted spell casting both drains mana and halts spirit-based regeneration.

Periodic Energize effects
A few items, such as Second Wind, as well as some spells, like Blessing of Wisdom, does not regenerate mana in 2 second ticks but rather in the intervals actually advertised in their tooltips. The five second rule does not apply to these effects either.

Additional notes

 * You do not regenerate mana faster if you are sitting down or standing up.
 * You do not regenerate mana faster in combat or out of combat.
 * Spell casting never stops direct mana regeneration effects from items.

Comparing direct and spirit-based regeneration
As described above, items can increase mana regeneration directly or indirectly, by increasing spirit. Due to the five second rule, together with the generally lower availability of good direct mana regeneration items, it is not always clear which type of regeneration is better.

The two types of regeneration can be compared by calculating their regenerative effect while mana regeneration is interrupted, as follows: