When their brains, now divided in two, are thinking the same thoughts, these Pokémon exhibit their maximum power.
– Pokemon White Pokedex
Duosion is the White exclusive Psychic Pokemon (the counterpart to Gothorita). Its name refers to the fact that it has two brains.
Both of its abilities protect it from weather damage (ie Hail and Sandstorm). Magic Guard is a better version of Overcoat, because it also protect Duosion from other forms of indirect damage.
Stat-wise, it has a lot of Sp Attack. At 125 base Sp Attack, Duosion has the highest Sp Attack of non-fully evolved Pokemon; It’s better than some fully evolved Sp Attackers’. Though its Sp Attack doesn’t change when it evolves. But this means its other stats are pretty low (save for HP, which it has alright amount of), especially its Speed.