There are 57 Mega Stones available in Pokémon Champions at launch, and you can obtain them via the Frontier Shop, Battle Pass ...
Operation Sports on MSN
Pokémon champions: How to get Aggronite
Turn Aggron into a tank!
Game Rant on MSN
How to Get & Use Mega Stones in Pokemon Champions
How to get, use, and equip Mega Stones for each Pokemon in Pokemon Champions.
There appears to be a problem at the launch of Pokémon Champions that is preventing players from using their Mega Pokémon.
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