I beg to differ. Once you get up to 50+ intellect, Death Star lvl 3 becomes very powerful. In the end of my mage game, it could inflict up to 9200 astral damage, which, as you can imagine, can wreak some serious havoc, even on impossible.
For a reference, my spells at the end had the following damage output values:
Armageddon - 11'650 max (astral)
Fire Rain - 6450 max (fire)
Fireball - 5995 max (fire)
Geyser - 9250 max (phys)
Phantom health: 93% (!!)
(This is with 58 Hero intellect + 10 from scroll, so 68 total)
So I would dare to state with absolute certainty that the mage in KBAP becomes really, really great nuker as the game progresses and that battles do end up in a few turns thanks to the new intellect system and the overpowered chaos spells.
__________________
|