Nintendo has revealed how it will distribute the missing Mega Stones which Pokemon can hold in Pokemon Sun and Moon.
According to information posted on Serebii (thanks, Nintendo Everything), these missing Mega Stones for Pokemon Sun and Moon will be handed out as presents to those participating in Online Competitions.
These include the 2017 International Challenge February competition, which will distribute Mega Stones for Mawilite and Beedrillite. Serebii notes a “limited amount of players” will receive the code ahead of a one to two months wait period before other Sun and Moon players are handed the Mega Stones code.
Another way players will receive codes for the stones is through various events and online postings. These will not have a wait period attached. The distribution of these codes will vary depending on the Mega Stone, and players can expect the same method of distribution for the codes through summer.
Mega Stones able to be used by a specific number of Pokemon during battle, and when held, it turns them into mega powered-up versions. Once the stone is removed, they revert back to normal.
The mechanic was first introduced in Pokemon X and Y and was also made available in Pokemon Omega Ruby and Alpha Sapphire.