KremePuff

In casual standard, it is true. In casual duels, you can.

Blizzard: you need to craft shitty legendaries that don't see play if you want to get to get all the achievements Also blizzard: fuck no you can't gain achievements playing shitty decks in casual. You have to play shitty decks on ladder and ruin your rank. Like a man.

Basically what Nug said. You can only achievement hunt in ranked.

And casual duels! :)