There's a floating rates NPC script already in the rA repo: https://github.com/rathena/rathena/blob/master/npc/custom/etc/floating_rates.txt   Just change the OnHour labels to something else: OnClock<hour><minute>: OnMinute<minute>: OnHour<hour>: On<weekday><hour><minute>: OnDay<month><day>: This will execute when the server clock hits the specified date or time. Hours and minutes are given in military time. ('0105' will mean 01:05 AM)