Carrion Eaters

a species that is considered monstrous by some
More of a sludge than a ridig shape, these creatures are often found around mass graves where they consume the bodies. Each body it takes in, it is then able to make a perfect recreation of how that person looked during life.
They spend most of their life in their natural state not having the intelligence nor the drive to use their body copying abilities for... more clandenstine activities.
There are times where bodies must be exhumed for legal purposes and when a carrion eater is found it can cause quite a stir for the local authorities when they are trying to square away their investigations.
Even more surprising is what happens to adventuring parties when go to retrieve one of their fallen allies! They think, "Oh hey, I have like 10 tens to go get that bag of bones. Then we'll be back to drinking with ol' Charles soon!"
But woe! Woe to that haughty adventurer. Their friend has been visited by the carrion Eater!
After large meals the carrion eater will rest to digest that delicious meat, as I am informing you they are wont to do. And as they're relaxing, probably wishing they had a nice cool beverage, they will transform into the body they just ate. Then when the allies return to the dead they get tricked and bring back the carrion eater!
Now if you bring this body back to the temple for a resurrection they will be unable to perform it! Carrion eaters are alive obviously. You'd have to kill it first and then the temple would still charge you and you wouldn't even have your friend back!
So the moral of the story is poke your friend with a stick to make sure they are really dead. Like actually dead. But! Sometimes your friend is only partially digested and you'll still be able to resurrect them even if the carrion eater beat you there. But hey, partial friend is better than no friend right?