Legandary dogs:

Catch slugma and battle with it until it learns yawn. When you fight one of the legendary dogs get them to low health and then use yawn. While it is sleeping use ultra balls gallore. If it wakes up use yawn again.

Good team:

Raiku
Entei
Suicune
Espeon
Ariodose
Noctowl

If you are stuck email me on pokefreak1029@hotmail.com