Mage/Dark Wizard Lvl 103 Mage Needs Help

As the title states, I'm a lvl 103 mage who needs help with a water build. The problem is I have Cascade as my wand and really don't want to change it.

I also have King of Hearts as a healing option, but while I would like to keep it, it's less necessary.

Can anyone help me out with a good build?

 

cascade (can dualwield king of hearts)

 

I personally don't like cascade, but here's a rainbow build for it. A water build on cascade would be kinda weird:
https://wynndata.tk/s/likx41
https://wynndata.tk/s/87hunk (Same build but lower damage, but better mana costs)

 

What's Rainbow Sanctuary? I've been looking on the Wiki, the Market, and Google and can't find anything called Rainbow Sanctuary.

 

https://www.wynndata.tk/i/rainbow+sanctuary