Legit Shaymin Without Event
I know, I know. Everyone always says that getting a Shaymin that is legit is only possible with an event. However, that is not true! I used Action Replay to get Oak's Letter, went through what someone who got the event did, and managed to catch myself a legitimate Shaymin!
How do I know my Shaymin is legit? Well, the Gracidea flower can only be given to a player that has an "Event Shaymin" in their party, and, while mine was gotten using the above listed cheat, I was still given the flower and it still transforms my Land form Shaymin into Sky form. Note that Sky form can only occur during the day and when the Shaymin is not frozen.