A great build is a fire and ice speedcaster. Since there is not much delay between casting spells and not many units resist both types of elemental damage, this build rips through enemies on higher levels.
Just use an atlantian magus and distribute the skillpoints evenly between willpower and intellect. In the beginning you have to use a hit and run strategy, but the more powerful you grow the more enemies you can take on at a time. Use frozen wind to hit enemies through walls so you can kill those safely, also when facing bosses keep a flash freeze at the ready to make an emergency escape and return when you've recovered. Don't get surrounded by enemies and fill up all your mana before moving to the next room.
The knight got several times a negative amount of leadership and health when lvld up! is that only a typo or does he really get weaker when lvling? That would explain why he dies first although best protected by guards.
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