The Pokemon master Ash must rescue his mother from the encasement of a crystal tower.
Barrierd (Hanako)
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Pokémon Trainer Satoshi has a new plan: see the world! But first, he and his partner Pikachu are headed to the opening of the Cerise Laboratory, a research facility dedicated to uncovering the mysteries of Pokémon in every region. Ash meets Gou, another boy with boundless curiosity about Pokémon, and both are overjoyed when Professor Sakuragi asks them to become official…
The mini-saga follows Satoshi venturing into an archipelago of islands called the Decolora Islands with Iris and Dent.
Source: Bulbapedia