Mage/Dark Wizard Need help with Fatal build

I need a spell spam riftwalker build with fatal, with low cost spells and high mana regen, entropy is also necessary

I have this arcanist build on, but i just don't like the arcanist playstile, and the costs are too high for adapting to riftwalker, and i've seen some riftwalkers that are the real definition of spell spamming, and i want to be like them when i grow up, please help :)

https://hppeng-wynn.github.io/build...Y02270e0o1f1g00001006CC1B1B05050D0D0-lNndtdV1
WynnBuilder build:
> Cumulonimbus
> Conduit of Spirit
> Dark Shroud
> Violet-Shift
> Summa
> Summa
> Diamond Static Bracelet
> Contrast
> Fatal [t6f6f6]
> (Has Tomes)

 

https://wynnbuilder.github.io/build...Y1527-H071G1g000010036C1B1B05050D0D0-l-RwhBx2
WynnBuilder build:
> Brainwash
> The Courier's Cape
> Ringlets
> Slayer
> Agave
> Summa
> Lachesism
> Contrast
> Fatal [t6t6t6]
> (Has Tomes)

the link has the same tomes with your original link
Agave is there for Winded stack efficiency
leftover sp is in str, invest on def or agi if more ehp is needed