Once you beat the Elite Four and get your sinnoh Dex. Go to Canalave City, and go into the sailors house, talk to the sick kid and his mom. Then, go outside and talk to the sailor who took you to Iron Island. Talk to him and he will take you to Full Moon island. Talk to cresselia. It will run, but track it with the marking map. Just use the same method that you used with Mesprit. If this doesn't help you, their are guides on the internet. (YouTube) GOOD LUCK!
If Cresselia disappeared off of your map completely, then you have already caught Cresselia, or there is a glitch in your game where Cresselia has just disappeared off of your map. Further details would be needed for a more in-depth assessment as to why this has happened if neither of the two reasons stated are why Cresselia isn't on your map.
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you do not!
no you do not
darkrai
After a little while into the post game, Cresselia starts appearing into your dreams or at least Darkrai is. He was pretending to be Cresselia. Cresselia is really good, but the Cresselia in the dreams are Darkrai's doing.
I looked it up, you can get Cresselia, but it doesn't say how. It only says you can get Cresselia at Sharpedo Bluff.
you find cresselia on full moon island
no, cresselia can only be caught in gens 4+
Well, Ice beam for a Choice Specs Cresselia and Icy Wind for a Cresselia with high stats on defense
If Cresselia disappeared off of your map completely, then you have already caught Cresselia, or there is a glitch in your game where Cresselia has just disappeared off of your map. Further details would be needed for a more in-depth assessment as to why this has happened if neither of the two reasons stated are why Cresselia isn't on your map.
because it was only one and not the whole colony of cresselia
Cresselia knows confusion, aurora beam, magical leaf, and slash
You get cresselia eventually once you beat all the treetops.
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WHAT WORLD ARE YOU IN!!! Nowhere does it say Milotic evolves into Cresselia!
Cresselia doesn't evolve and nothing evolves into it. So its just one Pokemon.