Kyogre,Rayquaza,Jirachi,Deoxys,Rotom,Uxie,Mesprit,Azelf,Dialga,
Palkia,Heatran,Regigigas,Giratina,Cresselia,Darkrai,Shaymin,Arceus.
How to catch: http://www.serebii.net/pokedex-dp/
you cannot catch wild rare Pokemon in xd but you can catch the trainers rare Pokemon, if they are "inpure"
You Catch it.
you can catch sudowoodo and smeargle
you cant catch it it is rare
You catch them. Or trade for them.
It is rare on One Island
tropius is a rare pokemon. but you can catch him near the water institute.
Rare Pokemon come randomly when you're in the grass or cave.
entai- legendary dog Pokemon
there are codes for rare and legendary pokemon.
Well it depends. A Pokemon with a higher catch rate means its easyer to catch. Rare Pokemon usally has a low catch rate. Go check serribi pokedex to check catch rate. Hope it helps!!
If you have rare Pokemon then no. But if you can remember how to catch the rare Pokemon then yes.