A.

Choco/Mog: Chocobo Farm
Shiva: From Priscilla in Junon
Ifrit: After defeating Jenova Phase#1 on the Shinra Ship
Ramuh: Chocobo Racing Room at the Gold Saucer
Titan: In the Gongaga Village Reactor
Odin: Safe in Shinra Mansion at Nibelheim
Kjata: Sleeping Forest
Bahamut: After defeating the Red Dragon at the Temple of the Ancients
Alexander: Defeat Snow at the Great Glacier
Neo Bahamut: Whirlwind Maze
Leviathan: Defeat Godo at the Wutai Pagoda
Phoenix: Fort Condor
Hades: Underwater Shinra Plane
Bahamut Zero: From the Blue Huge Materia obtained from the Rocket, you can recieve it at Cosmo Canyon's observatory.
Typoon: Ancient Forest ( you must defeat Ultimate Weapon first )
Knights of the Round: Northeast Cave ( you need a Gold Chocobo )
Master Summon: N/A


Q. When fighting the Materia keeper at Mt. Nilbel what Enemy Skill can you learn from him? And what Item do you recieve when you kill him?