There us no such thing as drift moon island. If you mean New moon island, you can only get there by a Nintendo event. If you mean full moon island, you have to gt the national dex and then go to canalave city. Talk to the boat guy and he'll offer to go to full moon where you release Cresselia. Cresselia likes to run like Mesprit though so you have to chase him through Sinnoh.
you go in my but
You find him on iron island in the cave
You cannot find the Pokemon Darkrai in Turnback Cave in the game Pokemon Diamond. Instead you can find him in Newmoon Island.
riolu
You find it in Orbegugh Mnes or on Iron Island
he is in the island when u get to canalave city
full moon island
in Pokemon diamond and pearl, its in iron island
you find cresselia on full moon island
at full moon island im finding out how to get there
no but you get the riolu egg in iron island
you find it on moon island or the resort area i think.....