Looks very powerful, but you won´t be able to cast a spell with >2 mana cost on the same turn, making this very vulnerable to weapon removal - still a very strong body though. Seems extremly strong, also: Neutral weapon!!! Now we can regularly enjoy the attack sounds of non-weapon classes (Although you probably don´t want to attack with the staff).
The card itself looks really good, a little slow at first glance but you still have a 7/7 on the board. When you face it, you pretty much have to choose: do i deny the value of the weapon or i clear the minion? some classes may have some hard time dealing with both at the same time.
And, not less important, as warrior is dominant, this card will actually make a lot of people tech Acidic Swamp Ooze and Harrison Jones, so it can result as an indirect nerf to weapon classes.
Very interesting design tho, i've been expecting similar weapon effects in a very long time
Edit: it's very sad that we cannot equip that with Malkorok :(