you get them in missions. in surrounded sea you get manaphy, although you cant recruit him.
Arceus isn't in Pokemon explorers of sky, so you can't recruit it. NO Arceus is in destiny tower floor 100!!!
get secret slab or m.part and go to mistefing forest 10 flor
Crystal Cave or Crystal Crossing
Manaphy isn't in this game he's in mystery dungeon explorers of Time & darkness or Sky
It may take several attempts to recruit legendary Pokemon in Explorers of Sky.
they ask you if they can be on the tam
No, there isn't.
mission recruit or egg
Take it as your partner Pokemon or recruit him at end lake
no but you will find the statue of arceus
you cant recruit him. there are only 492 Pokemon recruitible in the game
crevice cave and blizzard island, after you beat dialga
you cant recruit arceus he ain't a recruited Pokemon but when you get a space globe from his statue in destiny tower
you get them in missions. in surrounded sea you get manaphy, although you cant recruit him.
Recruit from Dark Crater or Mystery Part or Secret Slab
They help you recruit all the legendaries.