The dream world is a place where you can transfer (tuck in) your pokemon. The difference is most of the pokemon in the dream world have different abilites like lickitung having the ability Cloud Nine. You can also get pass orbs which creates pass power. There are 30 pass orbs you can get. (some of them are found in other people's worlds in the entralink) The reason why everyone wants pass orbs is because If you get 30 pass orbs your trainer card levels up.
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