You need time to set up your extortion racket, so use your removal spells to fight off creatures that pressure you. Angelic Edict and Murder handles the larger threats, while Blood Reckoning makes attacking you a dicey and dangerous proposition.

If you want to add a big finisher to this deck, consider Sublime Archangel from the Magic 2013 core set. This deadly Angel can fly over opposing defenses to deal massive damage. Another card to find is Obzedat, Ghost Council from the Gatecrash set. The guildmaster of the Orzhov, Obzedat is well-versed in taking an opponent's life and putting it to better use.

2 Basilica Guards
3 Basilica Screecher
1 Guardian Lions
1 High Priest of Penance
2 Kingpin's Pet
1 Knight of Obligation
1 Shadow Alley Denizen
2 Silvercoat Lion
1 Smog Elemental
2 Syndicate Enforcer
1 Tormented Soul
1 Treasury Thrull
1 Vizkopa Guildmage
1 Zombie Goliath

2 Angelic Edict
1 Blood Reckoning
2 Dying Wish
1 Executioner's Swing
1 Gift of Orzhova
1 Jayemdae Tome
1 Murder
1 One Thousand Lashes
2 Orzhov Keyrune
1 Purge the Profane
1 Rain of Blades

1 Orzhov Guildgate
12 Plains
13 Swamp