you guys..... your advice is really generic.
*splash blue for counters*
- wouldn't that be a solution for everything?
You have two concerns - a creature defense, and board sweepers.
This is what you do. You splash black.
First, for Wall of Souls. This, combined with Wall of Hope - (Or Wall of Essence) give a nice, "damage dump" - except when you dump damage onto the wall of souls, you get to do damage to them! This essentially allows you to get around their defenses. You attack, and either they let it go through, or they block, and you redirect all the damage to your wall of souls and make 'em pay for their insolence!
Also, black give you access to Duress and other discard, which can help keep the sweepers away. Further, a little Vindicate never hurt nobody!
Another stupid trick you can do with black is play with maddening imp, and force your opponent to attack into your en-kor army,bounce around the damage, then march victoriously into their tapped-out kingdom!
Finally, I'm ashamed nobody suggested Second Sunrise, as that's not even off-color. It wouldn't be a bad option in many match-ups anyway, because it essentially acts as a regeneration shield for those times when you have to dump a ton of damage onto your wall of souls and/or hope.