Ok... The first time you encounter Valvalis, she is not weak against anything (you cannot even cast on her while in her tornado). Fire, Ice and Lightning does the same amount of damage.
The second time you encounter her, she is indeed weak vs lightning (x4, instead of x2... ouch!)
So right... another boss is added to the list...
*Octomamm, Kainazzo, Odin, Leviathan, Valvalis*
Storm has to choose whether thornwithin or I win
