Materia is a crystallized form of lifestream energy. Although some basic types of materia have been created by the Shinra from Mako energy taken from the planet, the strongest can only be produced from the strongest concentrations of the purest lifestream energy. Materia is usually "junctioned" to pieces of armor or weaponry. Most types of materia have distinctive colors so that they can be divided into groups. However, some of the rarest materia have different colors completely.
Although there are many great pieces of materia, the most famous of them are: Holy, the White Materia, Meteor, the Black Materia, and Knights of the Round, the greatest of the creature summon magic.
Here are the types of materia:
Magic (Green): The magic materia is the most common. Using the knowledge of the lifestream, people can use this materia to simulate great effects, such as fireballs, ice storms, or even the remove spell.
Skill (Yellow): This materia gives the user knowledge to use special skills, such as enemy magics, or increased normal skills.
Summon (Red): The summon materia are the strangest of all. They are linked to certain magical creatures on other planes. They magically draw those creatures through a portal between the planes, similar to the Remove spell. Those creatures then fight for the user.
Individual (Purple-Pink): The individual usually effect the character or materia, but do not give spells, skills, etc. However, those that effect materia do not need to be "junctioned" to a single piece of materia to work just on that one. For instance, the most famous of these, Mega-All, puts the "All" effect on all materia held by the user.
Addition (Blue): The addition materias give special effects to the materia they are connected to on a piece of armor or weaponry.
Meteor (Black): This is the ultimate summon spell. However, it does not draw a creature from another plane. It is unsure exactly what Meteor does, or from where it came. Some say that it came with Jenova and is used to directly summon Meteor from space. Some, however, say that it was created by the Ancients to stop Meteor from coming, and that Sephiroth used it to banish that spell and allow Meteor to appear. Whatever the case, the Ancients bound it to their temple and set some "spirit" guardians. Meteor itself is a very small planet, that, similar to ours, is an entity made up of magical energy. It gains this energy by feeding on other planets' energy.
Holy (White or Green): Holy is the planet's ultimate defense system. Similar to the WEAPONS, when summoned it annihilates whatever is causing trouble with the planet. It is unknown whether the user must die or not for it to work, since Aeris is the only known user, and she was killed by Sephiroth as soon as she used it. Once summoned, Holy will turn a pale green color.
Magic:
Damage:
Ice: This materia allows you to cast Ice magic. It's useful against most enemies, but especially useful against fire enemies.
Fire: This allows you to cast fire magic. The reverse of ice.
Lightning: The lightning magic is similar to Fire and Ice, but is great against machinery.
Earth: The Earth materia is the fourth elemental magic. It is great against almost all enemies that can't fly.
Poison: The last of the main damaging materias, it is great since it hurts enemies directly and casts poison on them. Very strong vs. humanoid opponents
Gravity: This materia takes 25, 50, or 75 percent of enemies HP away. Great against most non-boss monsters.
Comet: Hits enemies with non-elemental damage. Good vs. single very strong opponents.
Contain: Contain is a very useful materia. It's spells generally wound enemies and hit them with a status effect (except flare). The most useful one, in my opinion, is Freeze, which hurts enemies and stops them.
Ultima: This magic hits all enemies with extreme damage.
Status Attacks/Defenses:
Seal: This prevents enemies from attacking or casting spells.
Transform: This materia can turn enemies into frogs and make them very small.
Mystify: Use this to make enemies lose control. It can make them only attack normally, or attack each other.
Time: This magic can speed you up, slow enemies down, or paralyze enemies completely.
Heal: This magic stops status changes. Poisona only stops poison. Esuna gets rid of most status effects, and resist can be cast to stop status effects from effecting you at all.
Destruct: DeBarrier gets rid of any barriers enemy may have put up. DeSpell gets rid of all defensive spells. Death kills an enemy instantly.
Defense:
Restore: This materia heals your characters directly, except for regen, which heals them gradually.
Revive: Life 1 restores life to one character, but leaves him with very low HP. Life 2 restores life and HP.
Exit: Escape is similar to running away, except you can do it instantly, and in the middle of pincer attacks. Also, sometimes you can use it to escape bosses like Ruby WEAPON. Remove sends all of your enemies to an alternate dimension, similar to all-death, but more likely to work. Generally, it will only work on enemies that come in groups.
Fullcure: Cures targeted character up completely.
Shield: Similar to wall, spells do much less damage.
Skills:
Steal: Allows you to steal items from enemies. Especially useful once it turns to MUG.
Sense: Shows you the enemy's level, HP, MP, and weaknesses. Mostly only useful on bosses. Throw: This materia isn't that useful, although it can do a lot of damage, and with Mime, that can be quite useful, especially since Mime doesn't cost you another item... weird.
Manipulate: This materia is very useful for gathering enemy skills, especially ones where you can't get them without it.
Deathblow: A useful materia. Although hard to use early in the game, late in the game it can be a prime boss killer. Plus, if you have a Mastered Mega-All or All attached, it can hit all opponents. Deadly.
Morph: This one isn't too useful, if you kill an enemy with it, you can get an item. Other than a few special enemies, generally you don't get anything different than you do with steal.
Double Cut: Hits enemies two times (1st level), or four times(2st level).
Slash All: Quite useful, this hits all enemies with the normal attack. On second level, becomes "Flash," which is instant death to all enemies. However, flash isn't very useful since on bosses it wouldn't work, and then you wouldn't have a normal attack. The Slash-All piece is nullified once Mega-All comes along.
X Magic: You can cast two magics on the same turn. Very good with 2nd level Quadra Magic, eight hits for one turn!
X Item: This allows you to use two items at once.
X Summon: You can summon 2 beings at once.
Mime: Copies last thing done for free, except limits, which can only be mimed by the one whom that limit is owned by.
Enemy Skill: In my opinion, the most useful skill materia. Get 24 spells for the price of one.
Summon:
Choco/Mog: Wind elemental attack that paralyzes opponents.
Shiva: Ice elemental attack.
Ifrit: Fire elemental attack.
Ramuh: Lightning elemental attack.
Titan: Earth elemental attack.
Leviathan: Water elemental attack.
Alexander: Holy elemental attack.
Kjata: Tri-elemental attack.
Odin: Strong non-elemental attack on one opponent or instant death on all opponents.
Hades: Non-elemental damage to all opponents and status effects.
Phoenix: The great bird of flame. Fire damage on all opponents and Life 2 on all characters.
Typhoon: Very strong wind-elemental damage on all opponents.
Bahamut: King of the dragons. Strong non-elemental attack on all opponents.
Neo Bahamut: A stronger version of Bahamut.
Bahamut ZERO: The king of Bahamuts. Super-strong non-elemental attack on all opponents.
Knights of the Round: The strongest of all of the summon spells. Summons 13 of the strongest knights, each that do damage about equal to Bahamut ZERO.
Individual:
Cover: Character equipped with this defends others.
Chocobo Lure: Attracts chocobos on chocobo tracks to user.
Long Range: Allows damage to be given far away from the opponent.
Counter Attack: Counter Attacks sometimes when hit by enemy with normal attack.
Enemy Lure: Attracts enemies.
Speed Plus: Increases speed of user.
MP Plus: Increases total magical energy of user.
HP Plus: Increases total life energy of user.
Luck Plus: Increases user's luck.
Magic Plus: Increases user's magical attack.
Gil Plus: Attracts monsters with more gil to user.
Pre-Emptive: Allows user to begin battle ready.
Exp. Plus: User learns more when fighting.
Enemy Away: Keeps most enemies away from user.
HP--MP: Switches magical energy and life energy.
Mega All: Works as though "all" is attached to every materia user carries.
Underwater: This materia is rumored to allow user to breath underwater and was used to fight Emerald WEAPON.
Support:
All: This magic makes the paired magic/skill attack/defend all enemies/allies.
Elemental: If put in armor, defends from paired element. If in weapon, attacks with chosen element.
Added Effect: Same as Elemental, except with status effects. Combine in weapon with Hades or Contain for strong status attacks.
MP Absorb: Drains MP out of opponent when paired spell is cast.
HP Absorb: Drains HP out of opponent when paired spell is cast.
Added Cut: Attack when using paired orb.
MP Turbo: Increases MP that it takes to use paired orb, but increases damage, too.
Steal as Well: Steals when using paired materia.
Magic Counter: Counter with paired summon/normal magic.
Final Attack: Cast paired materia when user dies. Very good with Phoenix, as it will damage opponents and cast Life 2 on all party members.
Quadra Magic: Casts paired magic orb 4 times for the price of 1. Use with W-Magic to cast it eight times.
Sneak Attack: Casts paired materia right at the beginning of battle.
Counter: Counters with attached skill materia.
COMBINATIONS:
Mega-All and as many magics and/or skills as you can fit in.
Final Attack-Phoenix
HP--MP,Knights of the Round(lvl.2, I think),W-Summon,Quadra Magic(lvl. 2)- This should be able to cast KOR eight times if you have over 2000 HP. However, I haven't tested it myself since I haven't gotten level 2 Quadra Magic.
All-Deathblow or MegaAll,Deathblow
Added Effect(Weapon)-Hades or Contain: Cause many strong status effects to enemies.
