How do you get Lugia in Pokemon Crystal?

Answer 1

You'll need Pokemon with surf, whirlpool and waterfall - and duplicate masterball (if you used it).

After defeating the Elite Four and the Champion, talk to the man beside the PokeMart in Pewter city. He will give you the Silver Wing key item. Take this to the Whirl Islands (between Olivine and Cianwood in Johto - you'll need a Pokemon with Whirlpool) and enter through the north-east entrance (top right island).

Jump the first ledge you come to, and then jump the top one when you come to a fork. Take the ladder.

This floor is straightforward - take the ladder at the end of the platform.

Pick up an item on this little island, then surf down the waterfall and you'll come to another island with a cave-door type thing in the wall. Go in, and surf across to Lugia. Save and engage in battle.

PS. You can also catch it with ultraball - just drop it health to minimum - next choose ultra ball in bag and save. Then throw, and load game if failed. It may take a lot of trials.
use the masterball.it never fails. for more info visit pokedream.com and select crystal walkthrough.
The same wat you do in gold or silver, go to the whirl islands and find him in that cave

Answer 2

You can get Lugia in Whirlpool Islands after a pokemon learn whirlpool and flash. You also need a silver feather when you talk to old guy in Pewter town.

N.B You need the silver feather or Lugia won't appear

Hope I help by Yung Redz