If I were to pick Sarkhan, not with the intention of putting it in my deck, but simply so that you won't get it, then I'm counterdrafting
From there, the upgrade path is as deep or as shallow as you want it to be
That said, it is interesting that this was originally part of blues color pie
Hand Size Matters Since you draw a bunch of cards you also need to pay attention to your hand size
There are 25 merfolk in the deck, five lords, and countless others that distribute counters to themselves and others
Both are also four-drops and they'll get any Swamp, even a dual land, but this is key in Black decks alongside Cabal Coffers and Cabal Stronghold and similar massive ramping from your Swamp count