The humans outside had no idea what was happening inside the World Tree Mystery Realm.
But people in every region noticed a strange phenomenon.
The Legendary Pokémon, normally so elusive, suddenly became wildly agitated, one after another.
And they were all rushing toward the same place as fast as they could.
"What... happened?" In the Kalos Region, Diantha watched Zygarde complete its fusion once again and fly off at top speed alongside Yveltal, murmuring in confusion.
"Lady Diantha, it seems something has happened to the World Tree!"
Beside her, Diancie suddenly spoke with a grave expression.
"The World Tree?" Diantha was taken aback. "Does something like that really exist?"
"Yes." Diancie nodded firmly. "I have the inherited memories of Queen First Diancie. Those memories tell me the World Tree really exists, but it seems to be in danger now."
Diantha looked up at the two departing Legendary Pokémon, and a sudden sense of foreboding rose in her heart.
What kind of danger could make two opposing Legendary Pokémon like Zygarde and Yveltal so anxious?
The Kalos Region was no exception.
The Galar Region's Pokémon Sword and Shield Kings and Eternatus, the Sinnoh Region's Time-Space Duo and Lake Guardians, and the Unova Region's Kyurem and Dragons of Truth and Ideals were all heading in the same direction at full speed.
The people of the Hoenn Region looked as though they had seen a ghost.
Because they saw Groudon riding on Kyogre's back.
What else could they call that?
Professor Oak said gravely, "With so many Legendary Pokémon acting strangely, this can't be anything simple. Something we don't know about must have happened!"
"Could it be those Shadow Pokémon that young Chen mentioned?" Professor Magnolia guessed.
Everyone's heart jolted at her words.
The more they researched dark matter, the more they feared