Pokemon Wi-fi Events

To get a mystery gift on D/P/Pt or any of the DS Pokemon versions, go to the TV Station, in Jubilife City, and go to the top floor. You should see a guy and a girl. When you talk to the guy, he will ask you for two words. Tell him, "Everyone" and "Happy." Then he will ask you for two more words. Tell him, "Wi-fi" and "Connection." Save your game after that. Then restart your game. You should then see "Mystery Gift" appear. When an event is being dealt with over wi-fi connection, click "Mystery Gift" then accept all things associated with it. Then start your game. Go to your nearest Poke Mart and talk to a detective-looking guy in front of the counter. MAKE SURE YOU HAVE AN OPEN SLOT IN YOUR PARTY FOR THIS.

Actually, you only need an open slot in your party if it's a Pokemon Distribution event. Otherwise, the gifts will be deposited into your bag ,or the main menu after the title screen depending on the event.