One word: Wobbuffet
He smashed up the Miltank. Mind you, Clefairy was a ***** because metronome bought on substitute >.<. Whitney was idioic and used both her super potions on clefairy so wobbuffet pwned miltank. Unforetunately wobbuffet did die with Miltank having (at a guess) 10 hp, but my onix came in and rock smashed (he was my only poke after I had tried to train weaker ones with clefairy, only being stopped by substitute). This was the fifth time I versed her so I was kinda getting deperate and then I thought, "Hang on. Pokewalker has a route with Wobuffet". So obviously I got him.
PS: Talking about pokewalker, I got flychu and surfchu as well with the yellow forest route. I'm sooooooooooooo lucky. :D