I am also trying mage impossible now and it works fine so far, i have already been at montero shattera and the demoen world at lvl 15.
I am using Beholders+Evil beholders + Red dragons as a tank with order 3/dis 2. ATM
1 mana heals full the dragon so if there are at most one stack of archers i can beat impossible stacks for now.
The Two beholder stacks are very important as they can disable and kill the low level units while the dragon tanks the high one.
For the last two spots i either use paladins (agains heroes as i do not have resurrect)
demonologists (summoned demons creates a lots of rage) or assasisn (because they are cool
)
I have 20 int ATM and trap 3 medal + trap arctifact. My traps do about 1k damage. Is this increases only by the Int or character LvL or if i upgrade to dis 3?
I like the Avanger Shield spell a lot, is is currectly doing a bit less than 1k damage, but 6 times. It also seems to trigger the Medal achievement 6 times, but i am not sure about this - i will check.
I really fear that on high level mage will be significantly harder than the warror.
To the OP: I think AP is easyer for No losses than KB:TL was.