My mages have intelligence of 14 - isn't this enough? And how am I supposed to know that higher intelligence means shorter cooldowns..
that's very low, but you should be able to cast minor heal every turn already.
get to 15-16 you should be able to cast blind every turn.
how do we know? as we level up, and play the game we notice cooldown time is reduced?
also, INT is mage's primary attribute, increasing the power and successful rate of spells. even if you can cast blind every turn with 15-16 int, the success rate against void dragon is quite low~