You'll realize getting 2-3 zombies can take hours. My last login I failed 6 times and got 2 successes (doing all the tricks of at night, in the graveyard, fresh corpse, etc). I didn't use the book but I got tired of carrying something so heavy.

And honestly, I can't think of a single character that I really "stomped" with an army. It was all warriors, assassins, paladins. The only one who really got destroyed was an elf conjurer I had 9 levels on and they didn't have sanctuary. My range was just bad for an army in general.