They get a certain amount of damage and they get incapacitated until the end of the battle or a certain amount of time.
If they receive a massive amount of damage and they die then instead of permanently dying they should resurrect at their point of origin and you must either pay or do some sort of quest from them to get them as a follower again.
This way there is a penalty and dont lose them forever.
If you are married to the companion then things would be a little different
What do you think of that?
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