That is right, but the past showed that shaman can deal with overload pretty easily, so I am confident about the power of the card. ^^

I agree with the lack of card draw, but Elemental Shaman can have a few cards that genreate others : fire fly, servant of kalimos, even the 0/1 taunt frog (but i don’t think it will see play in this kind of deck). Also, the elemental chain is not needed before turn 5 (i think) so playing a 3 drop elemental at turn 4 with 1 overload from a Zap the previous turn is totally fine. Anyway, this is a backstab with no restriction on the target, which is insanely good (and zero mana is a big deal, trust me). I even predict that it will see play in almost every shaman deck.

Zero mana = Tempo. Tempo = Win. This card = OP. Especially in Shaman.

Even with this, I don’t think Quest Shaman is playable.