SoCalCornHusker

very iinteresting deck.
have you considered, Traumatize ?
(target player mills half their deck rounded down)

Goblin Piledriver?
What do you think of Goblin Guide, Goblin Cohort, Mogg Conscripts, Mogg Flunkies, Bloodcrazed Goblin, or Goblin General ?

also, Hell's Thunder

Needle Drop is horrible, even Shock is better, than needle drop.

Lightning Bolt!!! Spark Elemental, Hellspark Elemental, Chain Lightning - Foil (if you can afford it)

Also Goblin War Strike is fairly innexpensive

What do you think of Mogg Conscripts, or Goblin Cohort?

Thought about adding Seeker of Skybreak (would make a decent combo with Imperious Perfect)

this deck has more forest than plains and should be the other way around...

What about Channel and Fireball?

Well, Steel Overseer looks interesting, but they are not exactly the same; Steel Overseer has to be tapped to activate the effect, whereas Arcbound Overseer Dosen't. But it's definately something to think about.

Arcbound Overseer. Gives a +1/+1 counter to all your Modular creatures during your upkeep.
=)

So... the only way to get Progenitus out is if you play Green Sun's Zenith...

Sideboard limit is 15 cards, no more or less