This mysterious Pokeball was given to Ash and friends by Professor Ivy in season 2 and it was kept with them until given to Professor Oak at the end of season 2 and when he couldn't figure it out he decided to give it back to Ash to take it to Professor Kurt in Azalea Town. In the middle of season 3, Ash and friends reached Azalea Town and gave it to Professor Kurt who was a Pokeball expert. Then the GS Ball was never heard from again. Any speculations to what this mysterious Pokeball may have held? Or if we may ever see it again?
The GS Ball.
The GS Ball.