I don't know what to say to this. Given more time and effort I could probably make this much better, and I WILL redraft it some day. But not today.
Trapped
"Where are my seedpods?" Celebi shrieked at the top of her tiny lungs. The surrounding plants and rocks just sat there. They did not know and they did not care. Why should they?
It was hard, being insane.
Eye twitching, she charged at the rocks, trying to stop their endless mirth. The rocks, however, grew legs and leaped out of her way. Chortling, they ran off into a swirling orange vortex and disappeared with one final snicker. Celebi shrieked again and flew at the trees, but she passed straight through them and found herself over an erupting volcano. Every speck of ash, every fleck of molten rock, every particle of black smoke, they were all laughing at her attempts to capture the rocks.
Despite that the volcano was erupting directly under her, Celebi felt no heat. No, she was cold; always cold.
The green fairy released a powerful bolt of psychic energy into the volcano, watching it pass straight through, never striking anything. Celebi let herself freefall into the bubbling lava, hoping that her eternal nightmare would end. But why should it? It had lasted for countless eons, why should today be any different?
Why did she have to live here? Why was she trapped in this endless torment?
The volcano gave way underneath her as all matter had. Instead of swirling red and orange, the black vastness of space opened up, billions of stars visible in every direction; pinpricks of light in the endless darkness. But then every one of them was snuffed out of existence, as if a giant monster had turned off the light switch for each one, leaving Celebi in total nothingness.
Everything vanished, it always did. Even her own touch no longer felt real.
And then the sound started assaulting her ears again. The impossibility of the situation was lost on the legendary Pokémon. Nothing was impossible anymore; that word had lost its meaning a few days after she had been captured.
She would make him suffer through this. She swore it with every passing second. Every time she failed to take a breath, every time she did not die of starvation. Every time she was reminded of what her world was. Just an illusion. Trapped inside the GS Ball.