Land destruction is probably the most hated strategy in all of Magic. There's basically nothing worse than sitting down to play a nice game and being unable to actually do anything. If this deck has its way, you won't cast a single spell. I love it.
It all starts with Crack the Earth and Smallpox, two effects that are supposed to be symmetrical. Flagstones of Trokair is the best way to break that synergy, but did you ever think to try Chromatic Star? Nihil Spellbomb works too, but it requires a tax of one black mana. I would say the vast majority of the time, these effects are going to work in your favor.
Liliana of the Veil is kind of a no-brainer in a deck like this, although I'm surprised to see only two copies. Once you cast a Crack the Earth or Smallpox, there's no card you'd rather follow those up with. Myth Realized plays the role of finisher, although it's also backed up by some planeswalkers. I really enjoy the choice of finishers because they are all difficult to deal with in their own way.
Go forth and make your opponents miserable!