>>17149248HA = Hidden Ability. Also called Dream World Ability due to the fact that this was orginally the only way to get them
later the secret groves in BW2 and Dream Radar allowed you to get them as well.In Gen VI, the only way to get them is through the safari or getting lucky with hordes.
HA's are sometimes the desired ability for the pokemon or the only ability that makes them viable (see Talonflame)
