The Goal is to give your opponent with Naganadels GX-Attack many prize cards, so he will lose, with no more cards in his deck. With Vaporeon's ability, Naganadel-GX is a Water-Pokémon and then you can use Misty&Lorelei, to reset Naganadels attack. You must discard cards to use Misty&Lorelei's effect, so you can discard the Exeggcute's and then with their ability you can take them from your discard pile back onto your hand.