NO!EDIT; Okay, that answer is really rude, so I'm going to answer it... Yes, you DO need to do the Mystery Gift option with a friend, because it wouldn't make much sense to send and receive a gift to...
No you don't get it from a friend, you have to set up Wi Fi on the main menu then wait for ninteno to relase a new event.
you do a poo.
u can use Pokemon battle revolution to do it or go to game stop and bring ur game and ds with and thyll give u a legendary
go into farmville and on the bar at the top of the game click on "free gifts" then click the mystery box and choose who you want to sent it to