Pain Skull -is it worth it?

[Leind]

dunno how I will do as a mage cut to 75 mana tho.

I got it just before Demonis, and so far after cleaning the last creep of the dwarf underground and Demonis I got it at 39%.
To survive as a mage with 65 mana (in impossible) I found trap and mass shackles + dryads to be very helpful in Demonis.

Without their magic ability the high level demon troops are just slow melee, easy to control with trap + thorns summon + slow & the spirit abilities. The only shooter are lvl2 and can be put asleep indefinitely if you split your driads in two stacks.
Greens Dragons are also great to regen some mana in combat, and against the other dragons they are great with the combo catching attack + trap.

I also got the Gremlins castle to use to get it down a little more