How could you catch latias if it keeps moving

wobbuffet prevents any Pokemon from escaping a battle.catch wobbufet's (and have a flying Pokemon) and go looking for latias.buy revives just in case they faints.for me pokeballs worked better than great and ultra balls.and you can catch wobbuffet at the safari zone in the first grass place you see.YOU CAN ONLY FIND LATIAS AFTER BEATING THE ELITE 4.