Before I ran Burning Wish, I ran both Terminate and Smother and Pulse and Fires and Putrefy. The deck was super strong, but you had no way to access any of your board cards. (you couldn't fetch anything).
The reason why I cut Terminate is because if you're not on Mox Diamond, you'll usually fetch for a basic Forest so you can continue to Loam. Then, with Smother, you only need any source of black to make it active. With Terminate in this case, you'd need 2 other lands. Obviously every gets to live the dream and draw Mox Diamond every game and have perfect mana, but I play against a ton of Crucible lock, 43 Lands, and a bunch of other decks where I don't get to fetch what I want when I want it.
Obviously, if you have 4 2-CMC removal slots, then run 2 and 2. If you only have 2, Smother is easier on your Manabase, but Terminate hits everything (except Iona on black, Blightsteel, and Spinx of the Steel Wind).
-Matt

