If the overkill effect stacks per minion, this spell is pretty decent with the chance to refill your hand. If the overkill effect doesn't stack per minion, this spell isn't worth running. Every other version of this type of clear is either better or cheaper than this, so I am hoping that that former is true
I would not dismiss this as easily. This can also overkill your own minions. As someone stated, it stacks well with celestial emissary but also with any 1/1 token generators. Depending how often you can get 2+spells, this might be better than people think.