In Ash's world he goes on to finally win the pokemon world cup.....right as he's about to claim the trophy, people start disappearing, one by one, he says his goodbyes, and he's left standing alone in the darkness....then pikachu comes running towards him, growing brighter and brighter.
Cut to his hospital room.
We see his mom at his bedside, crying, the doctor looks upset. apparently there's been no change in his brain chemistry for seven years, and his insurance has run out. with professor oak there to comfort her, she signs tohe release to have the plug pulled.
Shortly after the plug is pulled, he speaks these final wwords before falling dead.
"I wanna be the very best....."