He's trying to keep the deck standard, which is awesome as I was looking to make a standard Kor Deck and this should be a good base. You should add Stoneforge Mystic and some more equipment in place of Windborne Charge and other things that don't work towards pumping up your Kor with equipment.
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Have you considered adding Conquering Manticore?
Why not just add in more red zendikar fetchlands? Even if you don't want to drop the money for them, other's who are interested in this deck might; you can just make note of using terramorphic as a cheaper alternative.
If you're going for polymorph, I don't see the point in putting Ulamog in the deck when you don't get to utilize his ability as you are not casting him. Instead, put in Emrakul and swing with a 15/15 flying annihilator 6. I'm not sure about the choice of Iona either; it will help against a mono color deck, but against anything multicolor decks, she loses some effectiveness. I like what It that Betrays does, but I would honestly just put in 2 Emrakul and get him out as fast as possible. You can leave in It That Betrays if you enjoy the flavor of that card a lot.
I'm curious as to why the terramorphic expanse is in this deck?
Might consider Xathrid Demon in place of Lord of the Pit, as well as Priest of Gix for a free sacrifice drop.
A creature that is pacified can still tap for abilities, activate it's own abilities, and be sacrificed/the target of spells, while an exiled creature cannot. That is why I chose JtN over Pacifism. If I'm using either of those for creature control, I want the card that locks down a creature.
I would suggest putting raid bombardment in this deck, as it really works well with Broodwarden + lots of spawn, although more than 1 Broodwarden will cause Raid Bombardment to lose it's main punch, it will still do a lot of damage if you can get the combo off.
Garruk is incredible for this deck, as he allows me to play him on turn 4, then use his ability to put another Kor Spiritdancer into play. If your creatures are strong enough, follow up with his overrun ability and that usually ends it. He also puts chump blockers/extra attackers into play, as well as sacrifice fodder, which when you have only one huge Kor Spiritdancer, is devastating. Elspeth would be very powerful, especially making your permanents indestructible (wow). But, being the budget player I am, I'll stick with Garruk. I'll make note of Elspeth vs Garruk. I'm also not sure if 3 Day of Judgments will be worth it or not. The chance that I draw one in a game when I don't have my combo running is significantly increased, but then when I do have the combo running, I'll be drawing more cards than I know what to do with, so I might end up sitting with 1-2 DoJ in my hand. Also, this deck is so incredibly vulnerable to mill, I don't think there is anyway to avoid it though, other than only drawing cards when absolutely necessary.
If your focus is to use umbras, 4x Kor Spiritdancer is a must. They add invaluable card draw and perfect synergy with aura gnarlid, as when you cast auras on spiritdancer, the spiritdancer becomes huge, making it a perfect blocker, while aura gnarlid becomes an incredible nearly unblockable attacker.
You might also consider adding 4 Eldrazi Temple, incase you end up having to hardcast them, or Eye of Ugin simply so you can search for them.
Since this deck isn't standard, I would suggest adding lightning greaves. http://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=209141 Gives your fatties Shroud and Haste, keeping them alive and allowing them to attack the same turn they come into play.