Map of the Day(could be also week or month):
Mobs on this map drop bsb at a low chance 0.21% additionally muh coins 0.2-1% and mobs give double exp. Drop chance based on total map mob count. Map changes on a weekly/daily/monthly basis. Could be random map or chosen by gms. This could also be used, to make old maps more interesting.
Regards Siocane