Most powerful damaging spells

[bukimi]

I wonder which damaging spell I should max up.

Is Ice Snake the most powerful one?
I remember good effects of it in The Legend...
(and works well on demons and dragons)

I am not playing a paladin with resurrection so Armageddon does not seem a good idea.

There is also a new spell Death Star which deals astral damage but 50 mana is far too expensive to make it worth it, isn't it?

PS. I am playing mage, impossible. No kiting, losses acceptable