If youre in mono black, consider Withering Boon While its true that black deals with creatures rather well, there are some creature cards you really want to stop on the stack
You get to play a land each turn, but there are no limits to how many artifacts we can play in a given turn
So Emrakul is a fairly unstoppable card that threatens to kill people reliably in one of two ways and he does all this for a price less than a lot of cube cards that seem to do less
On top of that you can either use it as evasion by stopping your opponent's nasty blockers from taking part in combat, allowing you to squeeze through with lethal damage, or just attack without having to worry about the blocker's best creature
This card is a huge payoff for +1/+1 counter effects, especially if you have cards like Good-Fortune Unicorn around
The Creature will be gone for good, one of your opponents will be stuck with the unlucky Artifact, and youll get a Treasure, too