Mana is the primary resource for playing spells. Mana is typically drawn from lands, but it can also be generated by non-land permanents and spells. The mana system, designed by Richard Garfield, is part of what makes Magic so succesfull.  
Mana is the magical energy fueling spells of spellcasters. It is also deeply interconnected with life-force in every plane in Dominia, and it can take that role by itself as well. When there is no mana in an area, everything dies, and where mana's density is very low, lifeforms become emaciated and weak. 
The term Mana to denote an energy resource tied to land that allowed Magic to function was invented by science fiction author Larry Niven in his The Magic Goes Away series. Designers of the Magic card game gives a nod to Niven with the Nevinyrral's Disk card and the lich character Nevinyrral (Niven's name spelled backwards).
Colors of mana
- See also: Numbers and symbols.
Mana is primarily divided into five colors, but can also be colorless and have other qualities such as being "snow." Mana symbols are represented as images on cards and by letters in some print sources: 
- or S = Snow
- = colorless ("X" is a positive integer. Example: is 1 colorless mana, is 2 colorless mana and so on.)
Hybrid mana (also known as half-half mana) is a type of mana first introduced in Ravnica: City of Guilds and featured throughout the Ravnica, Shadowmoor block and Alara Reborn. Each hybrid mana symbol represents a cost which can be paid with one of two colors. The hybrid mana symbol can be of any combination of two colors, or any color of mana and two generic mana.
Examples of Phyrexian mana.
Phyrexian mana is a type of mana first introduced in New Phyrexia. There are five phyrexian mana symbols, one for each color (, , , , ). A phyrexian mana symbol can be paid with one mana of its color or by paying 2 life.
During design for Planar Chaos, they considered using purple mana in the set to give the feeling of an alternate reality. Purple would go in between blue and black on the color wheel, and there would be different allies and enemies, where a color's allies were the two colors on either side of it, and its one enemy was the color directly across from it. Purple would have enchantment removal, but be be worse at it than white, and would have direct damage, but be worse than red. They would take countermagic and edicting away from blue and black to use in purple. Purple wouldn't get any green abilities, because green would be purple's enemy. In each Planar Chaos booster pack, there would be a purple card in one of the common slots, and an extra 16th card which would always be a City, purple's basic land.
However, they realized that people might be disappointed if there was a sixth color, but it didn't have anything new, and after a while they decided not to add purple.
Converted mana cost
The converted mana cost (commonly abbreviated CMC or CC) of an object is an integer equal to or greater than zero. It is determined by converting each colored mana symbol in the spell's cost to 1 (unless it is one of the hybrid mana symbols , each of which converts to 2), then adding the results to the colorless mana cost of the spell. (For example, spells with mana costs of and both have a converted mana cost of 3.)
The only case in which a spell's converted mana cost can ever vary is for spells with in the mana cost. When an object with X in the mana cost is on the stack, X equals whatever value was chosen for it when it was put on the stack. In any other location, X equals 0.
- See also: X.
A mana ability is either:
- an activated ability that could put mana into a player's mana pool when it resolves.
- a triggered ability that triggers from a mana ability and could produce additional mana.
A mana ability does not use the stack, and as such it cannot be countered or responded to, by either player.
Spells that put mana into a player's mana pool, such as Dark Ritual or Seething Song, are not mana abilities, and use the stack as all other spells.
From the Comprehensive Rules:
- 106. Mana
- 106.1. Mana is the primary resource in the game. Players spend mana to pay costs, usually when casting spells and activating abilities.
- 106.1a There are five colors of mana: white, blue, black, red, and green.
- 106.1b There are six types of mana: white, blue, black, red, green, and colorless.
- 106.2. Mana is represented by mana symbols (see rule 107.4). Mana symbols also represent mana costs (see rule 202).
- 106.3. Mana is produced by the effects of mana abilities (see rule 605). It may also be produced by the effects of spells, as well as by the effects of abilities that aren't mana abilities.
- 106.4. When an effect produces mana, that mana goes into a player's mana pool. From there, it can be used to pay costs immediately, or it can stay in the player's mana pool. Each player's mana pool empties at the end of each step and phase.
- 106.4a If a player passes priority (see rule 116) while there is mana in his or her mana pool, that player announces what mana is there. If any mana remains in a player’s mana pool after he or she spends mana to pay a cost, that player announces what mana is still there.
- 106.5. If an ability would produce one or more mana of an undefined type, it produces no mana instead.
Example: Meteor Crater has the ability ": Choose a color of a permanent you control. Add one mana of that color to your mana pool." If you control no colored permanents, activating Meteor Crater's mana ability produces no mana.
- 106.6. Some spells or abilities that produce mana restrict how that mana can be spent, or have an additional effect that affects the spell or ability that mana is spent on. This doesn't affect the mana's type.
Example: A player's mana pool contains which can be spent only to pay cumulative upkeep costs. That player activates Doubling Cube's ability, which reads ", : Double the amount of each type of mana in your mana pool." The player's mana pool now has in it, of which can be spent on anything.
- 106.7. Some abilities produce mana based on the type of mana another permanent or permanents "could produce." The type of mana a permanent could produce at any time includes any type of mana that an ability of that permanent would produce if the ability were to resolve at that time, taking into account any applicable replacement effects in any possible order. Ignore whether any costs of the ability could or could not be paid. If that permanent wouldn't produce any mana under these conditions, or no type of mana can be defined this way, there's no type of mana it could produce.
Example: Exotic Orchard has the ability ": Add to your mana pool one mana of any color that a land an opponent controls could produce." If your opponent controls no lands, activating Exotic Orchard's mana ability will produce no mana. The same is true if you and your opponent each control no lands other than Exotic Orchards. However, if you control a Forest and an Exotic Orchard, and your opponent controls an Exotic Orchard, then each Exotic Orchard could produce .
- 106.8. If an effect would add mana represented by a hybrid mana symbol to a player's mana pool, that player chooses one half of that symbol. If a colored half is chosen, one mana of that color is added to that player's mana pool. If a colorless half is chosen, an amount of colorless mana represented by that half's number is added to that player's mana pool.
- 106.9. If an effect would add mana represented by a Phyrexian mana symbol to a player's mana pool, one mana of the color of that symbol is added to that player's mana pool.
- 106.10. To "tap a permanent for mana" is to activate a mana ability of that permanent that includes the symbol in its activation cost. See rule 605, "Mana Abilities."
- 106.11. One card (Drain Power) puts all mana from one player's mana pool into another player's mana pool. (Note that these may be the same player.) This empties the former player's mana pool and causes the mana emptied this way to be put into the latter player's mana pool. Which permanents, spells, and/or abilities produced that mana are unchanged, as are any restrictions or additional effects associated with any of that mana.
Mana Cost and Color
From the Comprehensive Rules:
- 202. Mana Cost and Color
- 202.1. A card's mana cost is indicated by mana symbols near the top of the card. (See rule 107.4.) On most cards, these symbols are printed in the upper right corner. Some cards from the Future Sight set have alternate frames in which the mana symbols appear to the left of the illustration.
- 202.1a The mana cost of an object represents what a player must spend from his or her mana pool to cast that card. Unless an object's mana cost includes Phyrexian mana symbols (see rule 107.4f), paying that mana cost requires matching the color of any colored mana symbols as well as paying the generic mana indicated in the cost.
- 202.1b Some objects have no mana cost. This normally includes all land cards, any other cards that have no mana symbols where their mana cost would appear, tokens (unless the effect that creates them specifies otherwise), and nontraditional Magic cards. Having no mana cost represents an unpayable cost (see rule 117.6). Note that lands are played without paying any costs (see rule 305, "Lands").
- 202.2. An object is the color or colors of the mana symbols in its mana cost, regardless of the color of its frame.
- 202.2a The five colors are white, blue, black, red, and green. The white mana symbol is represented by , blue by , black by , red by , and green by .
Example: An object with a mana cost of is white, an object with a mana cost of is colorless, and one with a mana cost of is both white and black.
- 202.2b Objects with no colored mana symbols in their mana costs are colorless.
- 202.2c An object with two or more different colored mana symbols in its mana cost is each of the colors of those mana symbols. Most multicolored cards are printed with a gold frame, but this is not a requirement for a card to be multicolored.
- 202.2d An object with one or more hybrid mana symbols and/or Phyrexian mana symbols in its mana cost is all of the colors of those mana symbols, in addition to any other colors the object might be. (Most cards with hybrid mana symbols in their mana costs are printed in a two-tone frame. See rule 107.4e.)
- 202.2e An object may have a color indicator printed to the left of the type line. That object is each color denoted by that color indicator. (See rule 204.)
- 202.2f Effects may change an object's color, give a color to a colorless object, or make a colored object become colorless; see rule 105.3.
- 202.3. The converted mana cost of an object is a number equal to the total amount of mana in its mana cost, regardless of color.
Example: A mana cost of translates to a converted mana cost of 5.
- 202.3a The converted mana cost of an object with no mana cost is 0.
- 202.3b When calculating the converted mana cost of an object with an in its mana cost, X is treated as 0 while the object is not on the stack, and X is treated as the number chosen for it while the object is on the stack.
- 202.3c When calculating the converted mana cost of an object with a hybrid mana symbol in its mana cost, use the largest component of each hybrid symbol.
Example: The converted mana cost of a card with mana cost is 3.
Example: The converted mana cost of a card with mana cost is 6.
- 202.3d Each Phyrexian mana symbol in a card's mana cost contributes 1 to its converted mana cost.
Example: The converted mana cost of a card with mana cost is 3.
- 202.4. Any additional cost listed in an object's rules text or imposed by an effect isn't part of the mana cost. (See rule 601, "Casting Spells.") Such costs are paid at the same time as the spell’s other costs.
- If a cost has an "X" in it, the mana cost equals the amount announced as part of playing the spell or ability while it is on the stack, but if the card in any other zone, X is treated as zero.
- An in a cost is similar to the symbol , but the mana must come from a snow permanent. It can't be paid with mana produced by nonsnow permanents.
- When paying for , it matters only if the permanents that produced the mana had supertype snow at the time the mana was produced. Changes before or after that time do not matter.
- is not a color, you can't add to your mana pool, and "snow mana" is not a type of mana.
- Colorless is not a color. See Rule 203.2c.
- The mana cost of a spell on the stack is the mana cost printed on the spell or ability being played. Only the choice value of X affects the mana cost. Other cost modifiers do not alter the mana cost.
Obsolete Mana burn rule
- See also: Mana burn.
When a phase ends, any unused mana left in a player's mana pool is lost. That player loses 1 life for each mana lost this way. This is called mana burn, and because it is loss of life, not damage, it can't be prevented or altered by effects that affect damage.
Mana Burn has been removed from the rules since Magic 2010.
- ↑ Mark Rosewater. (June 05, 2006.) "As Good As It Gets", Daily MTG, magicthegathering.com, Wizards of the Coast.
- ↑ Mark Rosewater. ( May 23, 2011.) "Mana Action", Daily MTG, magicthegathering.com, Wizards of the Coast.
- ↑ On Shandalar mana was so dense that it gained consciousness, and every of its drawn amount could reflect itself in form of elementals.
- ↑ These effects can be seen in the Dead Zone and Time Spiral-era Dominaria.
- ↑ Mark Rosewater. (October 04, 2004.) "Change For the Better", Daily MTG, magicthegathering.com, Wizards of the Coast.
- ↑ The Color Purple: Daily MTG
Bamooore, Binary, Daftmouse, Filby, Fishysua, GWiZ665, GeoMike, Hunter61, Lithl, MORT, Magic Mage, Merope, Murgatroid99, Novasun, Object404, Oracle of Truth, Prodigal Sorceress, Promethean, RMS Oceanic, Silver Surfer, Sneakyhomunculus, Unistardust, Voice of All(MTG), Wickeddarkman, Zatnik