Now get creative with your option groups! Common monsters, minibosses, champions can all have separate option groups assigned to them in mob_drop.txt. limited by your creativity!
Consider these lines as an example for item_randomopt_group.txt
RDMOPTG_KNIFE,7000,RDMOPT_VAR_MAXHPAMOUNT,100,0
RDMOPTG_KNIFE,3000,RDMOPT_VAR_MAXHPAMOUNT,100,0,RDMOPT_VAR_ATKPERCENT,500,0
this would give a 70% chance to have +100 hp option, and a 30% chance to have +100 hp and +500% atk
this can get as complicated as you would like it to be!
small example.txt