M2011 card stabbing pain

[median]

Stabbing Pain*                   

Instant   
Target creature gets -1/-1 until end of turn. Tap that creature.
#118/249


almost fire // ice
You lose the pitchablility and the ability to zap two toughness hate bears.
You gain a cheaper casting cost and mono blackness. Making it fit nicely into ichorid, or any u/b list that doesn't want a third (or fourth) colour.
I like it, what are your thoughts.

[A_Outcast]

I'd honestly rather run darkblast.  Granted this is better against goyf/lodestone, darkblast can be recurred to deal with additional threats, plus it builds up yawg will.

[Andreas]

I would say it is also worse than Piracy Charm.

[Delha]

A few more points...

1. Fire can kill a pair of 1 toughness creatures.
2. Fire can go to the dome. Marginal, but occasionally relevant.
3. EOT Ice on their blue source to turn off Drain/Pierce/whatever.
4. Fetch Islands and still Ice something in a Shop match.
5. Ice cantrips.

The vast majority of your targets for this with Dredge also die to Darkblast. I'd assume the bonus utility of the latter being re-usable and a minor dredger overrides the gain from stopping tinkered bots.

I think that if you're absolutely dead set against including a Volcanic in your list, then yes, this is probably the closest substitute to Fire/Ice. I personally think the lost flexibility is not worth the tradeoff.