Summon
Materia

Choco/Mog
**: 2,000
***: 14,000
****: 25,000
*****: 35,000
MP Used: 14
Find At: Chocobo Ranch
Stats Affected: Magic power+1, HP Max-2%, MP Max +2%
Deathblow!!: Does a small amount of type-less damage to all enemies, and sometimes puts the enemies in the "stop" condition.
Fat Chocobo: This alternate version occurs randomly, about one time in sixteen. A giant chocobo falls from the sky and damages all enemies, doing slightly more damage than Deathblow!!
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Shiva
**: 4,000
***: 15,000
****: 30,000
*****: 50,000
MP Used: 32
Find At: Lower Junon
Stats Affected: Magic power+1, HP Max-2%, MP Max +2%
Diamond Dust: Does a small amount of Ice-typed damage to all enemies. This is about 50% stronger than Choco/Mog.

Ifrit
**: 5,000
***: 20,000
****: 35,000
*****: 50,000
MP Used: 34
Boss: Jenova-BIRTH
Stats Affected: Magic power+1, HP Max-2%, MP Max +2%
Hellfire: Does a small amount of Fire-typed damage to all enemies. This is slightly stronger than Shiva.
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Ramuh
**: 10,000
***: 25,000
****: 50,000
*****: 70,000
MP Used: 40
Find At: Gold Saucer (Chocobo Racing Event)
Stats Affected: Magic power+1, HP Max-2%, MP Max +2%
Judgment Bolt: Does a small-moderate amount of Lightning-typed damage to all enemies. This is slightly stronger than Ifrit.
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Titan
**: 15,000
***: 30,000
****: 60,000
*****: 60,000
MP Used: 46
Find At: Gongaga Meltdown Site
Stats Affected: Magic power+1, HP Max-2%, MP Max +2%
Earth's Anger: Does a moderate amount of Earth-typed damage to all enemies. This is slightly stronger than Ramuh.
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Odin
**: 16,000
***: 32,000
****: 65,000
*****: 80,000
MP Used: 80
Find At: Shinra Mansion
Magic Power +1, Magic Defense +1, HP Max -5%, MP Max +5%
Steel Bladed Sword: Odin attacks all enemies, instantly killing them 75% of the time. This attack does no regular damage.
Gunge Lance: This alternate version occurs when Odin faces an enemy immune to his instant death attack (bosses, for example). Instead, he pulls out his legendary spear and attacks one target for heavy damage.
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Leviathan
**: 18,000
***: 38,000
****: 70,000
*****: 100,000
MP Used: 78
Find At: Utai Pagoda
Magic Power +1, Magic Defense +1, HP Max -5%, MP Max +5%
Tidal Wave: Hits all non-flying enemies for massive Water-typed damage. This attack does more than double the damage of Titan.
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Bahamut
**: 20,000
***: 50,000
****: 80,000
*****: 120,000
MP Used: 100
Boss: Red Dragon
Magic Power +1, Magic Defense +1, HP Max -5%, MP Max +5%
Mega Flare: Does moderate-heavy type-less damage to all enemies. Slightly weaker than Leviathan, but strong against bosses with protection from typed damage.
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Kujata
**: 22,000
***: 60,000
****: 90,000
*****: 140,000
MP Used: 110
Find At: Sleeping Forest
Magic Power +1, Magic Defense +1, HP Max -5%, MP Max +5%
Tri-Disaster: Does heavy damage to all enemies in three waves: Fire, Ice, and Lightning. Much stronger than Bahamut and Leviathan.
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Alexander
**: 25,000
***: 65,000
****: 100,000
*****: 150,000
MP Used: 120
Find At: Ice Gate
Magic Power +1, Magic Defense +1, HP Max -5%, MP Max +5%
Holy Judgment: Does very heavy Holy-typed damage to all enemies. Stronger than Kujata.
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Phoenix
**: 28,000
***: 70,000
****: 120,000
*****: 180,000
MP Used: 180
Find At: Condor Fort Huge Materia Event
Magic Power +2, Magic Defense +2, HP Max -10%, MP Max +10%
Phoenix Flames: All dead characters are resurrected and their HP filled to the max. Does a moderate amount of Fire-typed damage to all enemies.
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Bahamut Neo
**: 30,000
***: 80,000
****: 140,000
*****: 200,000
MP Used: 140
Find At: Whirlwind Maze
Magic Power +2, Magic Defense +2, HP Max -10%, MP Max +10%
Giga Flare: Attacks all enemies with heavy type-less damage. The amount of damage (4,000-5,000) is constant regardless of the enemies' defenses.
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Bahamut ZERO
**: 35,000
***: 120,000
****: 150,000
*****: 250,000
MP Used: 180
Find At:Cosmo Canyon
Magic Power +4, Magic Defense +4, HP Max -10%, MP Max +15%
Tera Flare: Attacks all enemies with very heavy type-less damage.The amount of damage (6,000-8,000) is constant regardless of the enemies' defenses.
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Hades
**: 35,000
***: 120,000
****: 150,000
*****: 250,000
Find At:150
Find At: Downed Shinra Plane
Magic Power +4, Magic Defense +4, HP Max -10%, MP Max +15%
Black Cauldron: Does a heavy amount of type-less damage to all enemies, and randomly casts Sleep, Silence, Minimum, Frog, Slow, Confuse, and Paralyze on the survivors.
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Typoon
**: 35,000
***: 120,000
****: 150,000
*****: 250,000
MP Used: 160
Find At: Lost Forest
Magic Power +4, Magic Defense +4, HP Max -10%, MP Max +15%
Disintegration: Attacks all enemies for very heavy wind-typed damage. A bit weaker than Bahamut ZERO, but it looks cool.

Knights Of Round
**: 50,000
***: 200,000
****: 300,000
*****: 500,000
MP Used: 250
Find At: Round Island Materia Cave
Magic Power +8, Magic Defense +8, HP Max -10%, MP Max +20%
Ultimate End: Thirteen Knights of the Round Table attack all enemies at random, doing heavy type-less damage each.
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Master Summon
Sell: 1 (don't see why you would want to sell it though...)
Find At: Cosmo Canyon OR give the guy in Kalm the Earth Harp for complete set of Master Materia
Stats: ---
Allows the character who has this item equipped to cast any summon spell in the game. You can only get this materia when you have at least one of every single other summon materia at master level. This materia does not gain AP, and can not reproduce itself.