Actual hearths showing actual health points: CHECK
Shield deflecting attacks from enemies in front of the character: CHECK
Pushing enemies around with the shield: CHECK
Now lets relax a bit and make the skeleton animated and facing it's moving direction. Then, the skull they leave on death will be a projectile, will land far from the player, and after a few seconds will grow a new skeleton if not crushed! Better dispatch them quick and one by one, they may be slow, stupid and weak, they will be a real pain in large number.