They all have dreamworld abilities, so I presume that they are available, but how?
http://pokemondb.net/pokedex/dialga http://pokemondb.net/pokedex/palkia http://pokemondb.net/pokedex/giratina
Those abilities are available in an Event that hasn't been released. The date is unknown which is similar to the Kyurem event with the moves Ice Burn and Freeze Shock. Hope this helps...
Unreleased Event.
Its still unreleased, but the event thats about to be releasedis the one to get a eeveloution so check up on that one. ^_^
