Items, Mega Stones, #701
Mewtwonite X flings for 80 power, a Mega Stones item since Generation VI
PokéAPI item 701 of 2,223, Mega Stones category, Items pocket
Effect, in PokéAPI's words
Mewtwonite X: “Held: Allows Mewtwo to Mega Evolve into Mega Mewtwo X.”
Games
Mewtwonite X is listed in the text of 5 version groups, first in Generation VI
Game index by generation
IIIIIIIVVVIVIIVIIIIX
Named in
X and YSun and MoonUltra Sun and Ultra MoonLet's Go Pikachu and Let's Go EeveeSword and Shield