Well the Battle Engine I had in Darksville supported 131,068 monsters however the on in Rokeno is Going to support a whole lot less considering every monster will have its own individual hitpoints.
Ok here is how it works. In Darksville there was 2 options spell or attack. If you attack it would divide your level by 5 and add 1 to know how many attacks you get (For Example: If you were level 7 and you clicked attack you would swing your weapon 2 times) Then you had the Spell option. After clicking on the spell you want to use depending on what kind of spell it is you would attack certain monsters. (For Example some spells would SUPPOSEDLY hit all the monsters and others would SUPPOSEDLY hit all the monsters in the first group and some spells would only hit one monster in the first group.) Rokeno fixes the problem with SUPPOSEDLY it gives every monster its own individual hitpoints so when you cast a spell that hits more than one you are actually hitting more than one. Also, when a spell hits one group or monster, it lets you choose which one.
EDIT: It is really irritating tho when GM has a glitch like not displaying the PRINT command and when you get a beta to see if the fix works and then the no multiple repeat glitch hits you. You see the Battle Engine for Rokeno only doesn't work because of a glitch in the GM beta I am using.