Battle tree mega stones: absolite, aerodactylite, alakazite, garchompite, gengarite, glalite, gyaradosite, kangaskhanite, lucarionite, metagrossite, sablenite, salamencite, scizorite, sharpedonite, slowbronite
Event exclusive mega stones: audinite, beedrilite, blazikenite, mawilite, medichamite, mewtwonite X, mewtwonite Y, pidgeotite, sceptilite, steelixite, swampertite
Alakazite: Ancient Poni Path, after defeating champion
Blastoisinite: Battle Tree, from Red
Charizardite X: Battle Tree, from Red
Charizardite Y: Battle Tree, from Red
Venusaurite: Battle Tree, from Red
The rest are unobtainable.
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Z-crystals from trials: waterium z, electrium z, grassium z, firium z, normalium z, ghostium z, steelium z, dragonium z
Z-crystals from kahunas: rockinium z, groundium z, fightinium z, darkinium z
Poisonium z: Ancient Poni Path (From Plumeria after defeating the Team Skull Grunts)
Psychicium z: Haina Desert (after Acerola's trial, On the pedestal at the end of the path reached by following the stone stacks in the order 2-1-4)
Flyinium z: Ten Carat Hill (On a cliff overlooking the hollow, via the path blocked by a heavy boulder in the cave (requires Machamp Shove))
Buginium z: Shady House (Guzma's room, in the chest next to the chair)
Icium z: Mt. Lanakila (Cave: on a pedestal in the right side of the cave, reached by bearing right at every branch in the path from the initial entrance)
Fairium z: Vast Poni Canyon (Outside, after the third cave: from Mina on the bridge)
Event exclusive z-crystals: pikachunium z, mewnium z, snorlium z
Unobtainable z-crystals: marshadium z
Pikanium z: Konikoni City (From a woman at Lighthouse Point in the north of the city)
Aloraichium z: Seafolk Village (From the female Veteran inside the Steelix ship in the east for showing her an Alolan Raichu)
Eevium z: Royal Avenue (From Kagetora in the Thrifty Megamart after defeating all of the other Eevee users and Kagetora himself, after becoming Champion)
Decidium z: Malie Garden (From Kukui after defeating Guzma, if the player chose Rowlet) or player's house (From Hau after becoming Champion, if the player didn't choose Rowlet)
Incinium z: Malie Garden (From Kukui after defeating Guzma, if the player chose Litten) or player's house (From Hau after becoming Champion, if the player didn't choose Litten)
Primarium z: Malie Garden (From Kukui after defeating Guzma, if the player chose Popplio) or player's house (From Hau after becoming Champion, if the player didn't choose Popplio)
Tapunium z: Ruins of Conflict (after battling Tapu Koko)
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