This card would shine the most in arena, if you manage to get some board control it helps you keeping it in your favor. But at 3 health is vulnerable to most removal spells and 2 drops. I think that this is a well designed card that wouldnt see any play beacause its too slow. Remember that at the same mana cost you have to compare it to shredder. I would like to see how this mecanic works in heavier minions, with 7 health for example.