Death and Dying
Something I did for my son and his friends group was as a reward for their first adventure completed:
The mayor of the village they had saved sent them to see a mysterious hermit who gave them each magic tattoos with swirling patterns and strange animal-like icons. They were...
Have a look at the computer game Rune by Human Head Studios if you can. (You should be able to get the PC version v. cheap now.) It has some excellent cave structures.
CM.
Maybe it wasn't down to his hitpoints at all. The arrows could have been enchanted with the Poison or Contagion spells and/or the Wounding and human Bane traits.
That'd settle his hash in short order...
CM.