How is this possibly weak? 3 mana for 4 damage is the pretty accepted level and whilst this is slightly different since it doesn't go through taunt and leads to damage, you have the possibility to instead effectively heal for 8.
Actually a great arena card for druid, sadly its not so good in constucted format.
WTF? This is a removal when you in battle for the board and a perfect answer for face damage like hunter or shamans, versatility is very important in a game without sideboard, a least one will run in every druid deck, I bet.