and do you recall how bad it was? for you or your opponent?
I think that maybe it really need the non-rare wording (but do not forget that volunter can also call rare zero cost cards), but there are some other cards that are more helpful for your opponent than for you (Cursed amulet, Inspiration,etc.. )
maybe if there was more "non-powerfull" rares 0 cost cards the odds would be less intimidating for the use of danai present