Pretender goes *Poof*

[archaeolept]

Well, I know I've come across someone complaining of something similar, so I thought I would run this by the cognoscenti here.

Playing Jotuns on Karan map. Have a nice and beefy Son of Niefel pretender (F4A2W9E4). He, a couple Jarls, and a bunch of woodsmen attack a Jade Amazon province, right by my home and w/ a strong friendly dominion. The Amazons are decimated and the two sorceresses cast nothing of interest (barkskin and the like).

Enemy armies are routed.

Then the Last Jade unit is killed.

At that moment my pretender, who has been behind the lines casting spells (legions of steel, fire shield), and has 194 hit points, just goes "poof" and dies.

That's it. No conceivable reason at all as far as I can see. Is this a serious bug or am I missing some sort of possibility?

thanks