I found a pretty good one on Reddit.Context will help identify the right suggestions here.
What are you looking to get out of the lingering injury? Do you want them to be healed by cure wounds / lay on hands or not? Do you want realistic lingering injuries (I hurt my knee and it will never be the same again - brain injuries that permanently change how the brain works,
If a player has a PC they love and the PC gets hit and takes a lingering injury - what do you want their experience as a player to be? For example, a 3rd level paladin gets a lingering leg injury. What experience do you want them to have - how long should it be an issue? What types of changes to their experience might you want to see them experience? Is this pure mechanics driven or is it RP driven? Is this an opportunity for the player to explore what it would be like to have those challenges? Or is it more about creating more diversity in combat challenges?
Some good ideas in here. I might steal a few of these. What I have is pretty similar, but I like some of your stuff around reduced healing factor, and adding exhaustion levels.Here's what we used in a campaign a few years back:
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(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.