If held by a Sceptile, allows it to Mega Evolve into Mega Sceptile if its Trainer has a Key Stone. Each Trainer can only Mega Evolve one Pokémon per battle.
Unaffected by item negating effects (such as Embargo and Klutz). Item manipulating effects (such as Trick and Fling) cannot give Sceptile a Sceptilite or remove a Sceptilite from Sceptile.
Outside of battle
If held by a Sceptile, allows it to Mega Evolve into Mega Sceptile when it performs a Spectacular Talent during a Pokémon Contest Spectacular while its Trainer has a Key Stone. Sceptile will remain a Mega Sceptile until the Talent Round ends.
The player can obtain the Sceptilite by completing Mission Card 19.
The Sceptilite was also available as a prize during the Mega Sceptile Competitive Stage. This Competitive Stage ran on both the Nintendo 3DS and Mobile versions from April 5 to 12, 2016.
The Sceptilite enables the following Mega Evolution: