There are 2 Zigs and 2 slaughter houses. Borgoth the Bloodletter(slaughter house) and Masophet the Black(Zig) can spawn in either of their associated buildings. One of the slaughter houses is to the east on a hill, the other is in the center to the south. The two Zigs are on either side of the southern slaughter house.

Again, both of these Lts. have two spawn points.