How do you get Shadow Lugia on Pokemon SoulSilver?

First off, it's spelled Lugia. Second off, you encounter Lugia at Whirl Islands ofter obtaining the Tidal bell and Silver Wing items. You must then battle the Kimono girls, and go to Whirl Islands once your ready. It's a maze in there! Be careful where ya go! Just use your MasterBall on Lugia, by the way. Instant catch ^^ Good luck!

Lunarstar out!