
Death is Black's best strategy, pure and simple. No Black creatures are as peerless in decimating the enemy opposition as Xathrid Demon, Ob Nixilis, the Fallen, and planeswalker Sorin Markov.
Xathrid Demon is one of the 2010 Core Set's toughest cards. For six mana (3 black and 3 of any) you can summon this 7/7 demon with flying and trample. This alone makes Xathrid Demon a formidable fighting machine. However, at the beginning of your upkeep, you must sacrifice a creature besides Xathrid Demon. Each of your opponents loses life equal to the sacrificed creature's power. This allows you to throw your monsters at your opponent and quickly reduce their life to zero. However, Xathrid Demon comes at a price. If you can't sacrifice a creature during your upkeep, Xathrid Demon is tapped and you lose seven life. This is a high cost to pay if your side of the battlefield isn't ripe with small tokens or smaller creatures for Xathrid Demon to feed upon.
The hot Zendikar set introduced many beastly creatures, though none are more titanic than Black's Ob Nixilis, the Fallen. For five mana (2 black and 3 of any) you can summon this legendary 3/3 demon. In addition, Ob Nixilis makes flawless use of the landfall ability. When a land enters the battlefield under your control, any player of your choosing loses 3 life. Also after this happens, you put three +1/+1 counters on Ob Nixilis. You can keep this effect up for multiple turns, damaging your opponent while powering up your demon. What's more, if you put multiple lands on the battlefield under your control (by using Harrow, for example), you can use Ob Nixilis' powerful ability multiple times in one turn.
Planeswalkers are powerful cards, and each Magic duelist knows this. However, one of Zendikar's top cards was planeswalker Sorin Markov. For six mana (3 black and 3 of any) Sorin enters the battlefield ready to devastate. For +2 loyalty points--Sorin enters with 4--Sorin deals two damage to a selected creature or player and you gain 2 life. This allows you to eliminate your opponent's smaller creatures or wither your opponent's life force directly. For a big finish, and seven loyalty points, Sorin allows you to CONTROL YOUR OPPONENT'S NEXT TURN. You can do absolutely anything you please, even going so far as to tap all of your opponent's lands and do nothing until the end phase, causing your opponent to mana burn for a potentially fatal amount of damage. With Sorin Markov, the method of your victory are yours to choose.