I have r1 alchemy mastery and r1 rain casting but rF water alchemy. According to the wiki, it says that water alchemy increases the effectiveness of rain casting which is a bit vague. I was wondering if it affected the duration or the aggro reset capabilities of the cloud when you or your party members are under attack by monsters. It takes 30 seconds after the cloud is up for a monster to lose aggro on you or other party members. Is it worth ranking water alchemy to affect this or does it not affect the aggro reset at all?
Also, can two party members rotate between rain casting in a same room to control the multi aggro?