OK so first what you have to do (if you don't have any one with a move that can leave an enemie paralyzed or asleep) get a Pokemon that can put the enemy asleep or paralyzed without fail and without damage. I suggest a pikachu with the move thunderbolt or a drowzee with hypnosis. Get 20 Dusk Balls, 20 Timer Balls & 20 Ultra Balls. And get a pachirisu with the move Super Fang. First go to your first subject. I suggest going to uxie or azelf before mespirit. Use Pachirisu's Super Fang (Super Fang cuts the enemies health in half) until their is only 1 health left (you'll know because of how small the red bar will be). Next paralyze or make it fall asleep. Then use a ultra ball 40-50% of the chance it will instantly be caught only using 1 ball but the statistics can decrease depending on who your using it against. When I first learnt this myself i did this and when Uxie was on 1 health I used pikachu's thunder wave then only 1 Ultra Ball after that and it was caught.
Hope this helps
OK, I suggest if u have the TMs Thunder or Thunderbolt (which will make your foe paralyzed) Teach that to a Pokemon who can learn it and have lots of Ultra Balls. Azelf is located in Lake Valor (Use Surf and go inside cave), Uxie is located in Acuity Lake (Do same thing as above in "()"), and Mesprit should be located in Verity Lake. When in battle, use Thunder or Thunderbolt (do it only once), this should paralyze the Pokemon. Now is ur chance to catch them. (do not use Master Ball unless u have more than 3 Master Balls. If not use Ultra Ball.) If that doesn't work, when u r in the cave do not click on Uxie of whatever yet, save the game and if u fail to catch them, just simply turn off ur DS and try again.
-UxieMespritAzelf
after you catch your legendary Pokemon GO to the caves in the middle of the three lakes make them sleep and catch them but mesprit run away use your marking map and then catch mesprit
=no=
sorry man, but you cant get a azelf uxie or mesprit in Pokemon soul silver...
the way you catch azelf mesprit and uxie.
Catch them?
When you catch dialga/palkia or defeat them, you can catch azelf and uxie in the lakes.Mespirit will flee so you gotta get a poketech radar to track it down.
Mesprit Azelf Uxie Palkia
go to sunnyshore city if u haven't yet
they are the three legendary trio of lakes they live in three lakes azelf in lake valor mesprit in lake verity and uxie in lake acuity
No
you catch it at lake varity with the three of them mesprit uxie azelf
yes you can and you can catch them after you catch dialga/palkia/giratina
ALOTof ultra balls