how do i catch the three lake spirits? on pokemon diamond?

Answer 1

Like any regular pokemon you find in the wild? Use timer, dusk, ultra balls. If you feel lucky, use a quick ball.
They are lv 50 and are psychic type. Mesprit will be the only that will make you chase you around the world so you will want to have a pokemon with 100 speed and mean look to prevent it from escaping.
If not, you need a pokemon with quick attack, shadow sneak, match punch to whittle away its hp every encounter.

Answer 2

u need at least 50 ultra balls for uxie and azelf each. i would recomend using the masterball on mespirit just bcuz it keeps moving around if u try 2 catch it and fail. for uxie and azelf use the ultra balls. the spirits are in each of the lakes just use surf and go into the island in the lake and then catch them.uxie is in acuity lakefront,azelf is in valor lakefront and mespirit is in verity lakefront.