We don't have enough green to support Force Of Vigor, so I think Nature's Claim is out next best option.

Further 'free' interaction would be Force of Will, which should still be a consideration. Spell Pierce is also an option, one I've been trying. Solid so far.

@Hanni: I've tried both versions, and Death's Shadow/Street Wraith/Thoughtsieze are better than Tribe/Rootwalla/Therapy, period. My personal experience has shown that a turn 2-3 Shadow is much better than even 2 turn1-2 Rootwallas.

I definitely need to get more testing in, but so far I am much more positive about the shadow version. Daze offers so much, it's so good in this deck. This deck has alternative t1 plays that are just as good as a t1 blitz, starts that create better inevitability.