As you enter the Champion's Room, you come face to face with a mind controled Ash Ketchum. Mewthree, using Ash as a channel, curses you for coming this far and challenges you to a one-on-one battle.However, after beating him, the mind control does not break. Then Joey comes into the room with Ash's Pikachu on his head. Mewthree gets enraged and appears before you and claims that he will take everybody with him in some sort of suicidal attack. Just in time Mew appears and tell him that, since he is made from Mew's cells, Mewthree is his son. Mewthree finally finds peace and swears to repay for all the damage he caused. Then Ash and Joey start a musical act of Pokérap, with all the sprites of the 150 Pokémon appearing in the scene (Mew was not included in the Pokérap).
If possng all 3 starters at tBulbasaur evolution (e.g. Venus♙toise and Charizard) so you could easily defeat the 3 starters of Ash. Use a Level 83 or higher Gengar with Thunder and Psychic. First, Thunder until Primeape comes out. Then use Psychic until Primeape is gone. Thunder Pidgeot. Then Thunder Squrtile then use Psychic when Bulbasaur comes out. Finally, Thunder Charizard until dead. Don't forget to heal after Pidgeot. Rain Dance is optional. Good Luck! You only need a level 100 vaporeon with aqua ring and muddy water First: When choosing the team,make vaporeon use aqua ring Second:When Snorlax (or Other) apper,trade aqua ring for muddy water Three:Fun! OR Have a lvl.100 grass type that knows solarbeam and leechlife.