Pokemon Mystery Dungeon explorers of the sky how to recruit shaymin?

Shaymin can only be recruited after the story is complete. He requires you to have talked to Kecleon once in Mr. Kecleon's Shop and to have saved Cresselia. Then you will need to go talk to Shaymin in Flower Paradise and return to Treasure Town to inform Wigglytuff, who will tell you to go to the guild with the other members. Wigglytuff will then announce an expedition which will prompt Shaymin to join your team.