If held by an Altaria, the Altarianite allows it to Mega Evolve into Mega Altaria if its Trainer has a Key Stone. A Trainer can only Mega Evolve one Pokémon per battle (or only have one Mega-Evolved Pokémon at any given momentZA).
As a Mega Stone, it is unaffected by item-negating effects (such as Embargo and Klutz). Item-manipulating effects (such as Trick and Fling) cannot give or remove an Altarianite from Altaria.
Outside of battle
If held by an Altaria, allows it to Mega Evolve into Mega Altaria when it performs a Spectacular Talent during a Pokémon Contest Spectacular while its Trainer has a Key Stone. Altaria will remain a Mega Altaria until the Talent Round ends.
Erases all Pokémon within two spaces of the match. If more icons of this Pokémon are adjacent to the match, then for each additional icon, one more Pokémon is erased in that direction.
Mega Ring System Altarianite
Altaria, Mega Altaria & Altarianite metal charm set
Poncho-wearing Pikachu Pikachu in Mega Altaria poncho figure
Mega Altaria & Altarianite keychain
