Things You'll Need
Instructions
Connect your Nintendo GameCube or Wii console with your Nintendo DS via a GameCube-to-Game Boy Advance transfer cable. The systems have the same ports, so you will be able to use the cord even on newer versions.
Visit the second floor of any Poke Center in "Pokemon XD: Gale of Darkness."
Visit the second floor of any Poke Center in "Pokemon Pearl."
Talk to the first girl behind the counter in both "Pokemon XD: Gale of Darkness" and "Pokemon Pearl" and choose the "Trade" option. The game will detect the transfer cable and link the two systems.
Scroll through the list of available Pokemon and press the "A" button on "Lugia" in "Pokemon XD." Confirm the decision in the confirmation window that appears. Lugia will now be on your saved game of "Pokemon Pearl."