Mono-Shadow - ft. At Any Cost and Midnight Hunt

The basic idea here is to just play strong cards until your opponent can't deal with them anymore. We have a strong focus on building up shadow influence to 12, so you can just blast them with 12 damage for 3 mana (At Any Cost). This is why we have Grand Builder in the deck. If Acantha Ascending is in play, 8 shadow influence is also very relevant, since she can start forcing sacrifices. (By the way, don't forget that At Any Cost has Decay - that's relevant occasionally.) Midnight Hunt has a similar function, but it can provide a surprise lethal using any unit, and almost no one sees it coming.

Eremot, Mindsplinter can sometimes just win the game, if your opponent cannot answer him.

EDIT- I got the Awakening campaign, so I made some major updates to the deck. You can see the revisions below. Edit #2- made some changes based on things I felt were missing in my games, such as any all-purpose removal. I'll note that the version I'm actually playing has primal splashed into the powerbase (without losing any shadow at all), just so I can put Rindra's Choice in the market, as a reply to multifaction sweepers, like Nothing Remains.

One of the most significant changes was the inclusion of Karvet, Redeemed. He pushes us toward 12 shadow influence very quickly if not removed promptly. But even more than that, if he's combined with Severin of the Dark in the market ... that's a truly crazy combo. Minimum of three Piercing Grief every turn. (It's it's it's ... all your fault.)

The final change was adding some primal influence to the deck in order to play Rindra's Choice in the market. I had Feeding Time in there for a while as well, but it seemed too expensive. The card I most often pull from the market is Severin, but Rindra's Choice can negate Nothing Remains or Shen-Ra Speaks, so that's why it's in there. This approach also gives us access to Crest for scouting, and it disguises our true deck as well, so the opponent might not be expecting the At Any Cost that closes out the game. In fact, the funnest way to win (which has happened to me a few times) is 24 face damage for 6 mana. (Double At Any Cost)