Originally Posted by DampingEngine
If you really can't afford Sinkhole, I would recommend playing Choking Sands in its place. It has no chance to backfire on you unless you also have a Wasteland and they only have one nonbasic land, and you get greedy and want the 2 damage more than you want to destroy 2 lands. If you avoid that trap, it's the best black land destroyer after Sinkhole. Rancid Earth just has too great a chance to backfire in this deck. Nothing's as good as Sinkhole though, and it's worth your while to get some.
I have a question for Chris Pikula - would you consider dropping the 2 Engineered Plagues for 2 more creatures? I tested out the deck with the 4th shade and one random wretch main deck, and it was nice to have more creatures, and I just wouldn't play the deck without 4 shades so something had to go. I believe shade is one of those non-debatable 4-ofs that you mentioned, and I'm surprised you couldn't find room for the 4th.
One more question - did you not play Chains of Mephistopheles in your sideboard because of unavailability, not knowing it existed, or a concious choice? It's my favorite black sideboard card because it's the strongest single disruption card vs. decks like Gro and Solidarity, and it's usable vs. Landstill and many other decks as well. It's also neat in this deck because you can cheat it with Dark Confidant, and be the only player who gets to draw extra cards. I would understand not playing Chains if you thought your game was more than good enough vs. all those decks (it is pretty good), but even then, 2 or 3 Chains sided in would increase your chances even higher, which isn't such a bad thing.