I have done a few ironmans of FE6. One of which Rutger and Dieck died before the end of chapter 8x. Let me tell you this, without those two, Henning is a nightmare. Zealot has 30-40 hit with an iron lance even when he has the steel blade, and deals barely any damage. If I hadn't had a trained Lugh that could slowly whittle him down, I would have lost. I would have run out of heal staves and been unable to do that ironman there and then. I like bosses that are tough, but Henning's problem is that without one or two characters trained he becomes extremely difficult to nigh impossible to fight.