Things You'll Need
Instructions
Once on the island...
Once on Navel Rock, enter the cave and proceed north until you come to a ladder. The next room is small with another ladder going down. Follow the next path and don't take any paths that branch off from here. you will come to a fork.
Take either path. Both paths are long and the room repeats for three to seven floors. At the end you will find Lugia or Ho-oh. Save.
Put Lugia or Ho-oh to sleep and then attack. This will help you knock down their health without the threat of a sudden heal.
Use a Pokemon that knows the Surf, Icebeam or Thunderbolt move until their health is in the orange or red. You want to freeze them. If that does not happen, switch to a Pokemon that knows Sing or Sleep Powder and use it. Hurl Ultra Balls until they are caught. You may have to repeat this step if the bird uses "Recover."
Once you capture your desired bird, backtrack and take the opposite way to find the other bird. Repeat the battle step and both will be yours.