From PokéHeroes Wiki
A Dynamax Crystal is an item that allows certain Pokémon to perform Gigantamax evolution.
How to obtain them
- They can be obtained uncommonly by Pokémon bringing them back from a Galarian Rumble mission.
- They can also be obtained through Speed Click Saturday by exchanging 10 SC-Token for 1 Dynamax Crystal.
How to use them
- They can be used from your Item Bag by navigating to the Evo. Stones section.
- They can also be directly used on a Pokemon's Summary Page. That's if the Pokémon has a Gigantamax evolution and meets the requirements to perform its Gigantamax evolution.
- Dynamax Crystals are trade able.
- Gigantamax Evolution is not reversible.