You have to get the national pokedex, then go to Canalave City.
Palkia, Arcuise, Darkrai, Cresselia, Shaymin, Mesperit, Uxie, Azelf, Regigas, and Heatran.
You cannot breed Cresselia. Cresselia is a legendary Pokemon, and you cannot breed a legendary Pokemon.
you do not!
you find cresselia on full moon island
Cresselia is found in Pokemon Platinum as a roaming Pokemon. After encountering Cresselia for the first time, one can follow its location by checking their Pokedex entry for the Pokemon. Cresselia can potentially appear in any patch of tall grass.
Pokemon company
Yes!
You get cresselia eventually once you beat all the treetops.
Unown
cresselia
Cressilia is a psychic type Pokemon
Shiny Pokemon are different colorations of Pokemon you have a 1/8000 chances to see one when you find cresselia hopely its shiny.