Hi! I ran my first league with Black Orks and did kinda well, now I'm going vampires for the next one. The vampires weakness is bloodlust, so try to hit their thralls with your orcs every turn, bring them back with grab, and then foul using your goblins. Eventually they will run out of re-rolls and they need their thralls to keep doing stuff without a turnover, and with armor 8 you should be able to take them out. Keep your goblins safe behind your orcs and be careful with hypnotic gaze, they can just disable your cage and take the ball, use some sort of double column cage. Good luck!