There's definately multiple things against him here. Not only is this an elf, it's a low level elf (invoker) I'm guessing, which means he has low hp, no defensive skills, and is attacking one of the hardest hitting mobs in the Academy.

Ultimately, this becomes another skill among CF...learning which mobs are ones that hurt a lot...but only if they can hit you and are not so bad w/ martial or heavily defensive characters, compared to mobs that might not hit very hard...but do so much more often, which might be better suited for giants, or magey-priesty types that often have better damreduction.