If you've exhausted all possibilities and no matter what you try you just can't seem to kill Jon, and you've been at it for a long time with no success, you might want to consider the possibility that your party is too low level.
If your magic users can't use or don't have some specific spells that they definetely need (defense breaching spells, true sight, etc.) it can make this fight damn near impossible. After all, if you can't tear down Jon's defenses then you can't harm him in any way.
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a bunch of long hairs.
trux
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