BECMI Companion Set: Dungeon Master's Companion Book Two Only
Just the DM Book from the Companion Set.
Big thing is Domain Rules. Gives p
Also get extra-planar adventures, miscellaneous rules, monsters and magic items for going up to 36th level.
Monsters include the BECMI Beholder, Haunts (Banshee, Ghosts and Poltergeists), and the Manscorpion.
There are also three adventures to introduce the new procedures found in the Companion Set. The First for running tournaments hosted by domain lords, secondly the Unarmed Combat System, and finally big combats using the War Machine rules.