DFHack
Add option to `deathcause` to make the game treat a death incident as discovered
While deathcause can reveal the cause of death, it's not reflected in the game when memorializing units whose deaths have not been discovered. This may be justified if the corpses cannot be physically discovered e.g. fell into magma, drowned somewhere inaccessible, etc.
However, the deaths of non-citizens will never be discovered, even if the corpse was found or the moment of death was directly observed by the player's citizens e.g. militia kills an FB. When the dead unit is memorialized, it will state that the unit "went missing" instead of stating the actual cause of death which logically should already be known.
Changing the death's incident.flags.discovered to true will make it possible to engrave memorial slabs for non-citizens that state the actual cause of death.
I'm opening this issue partly as a reminder for myself for when I might have the time and mood to modify the script, though if anyone else wants to have a crack at it please feel free to run with my idea.
A question that we will need to discuss if this is implemented is whether this needs to be marked as an "armok" level manipulation. I personally do not think so, but I could be convinced otherwise, possibly
It could include checks to make sure that the death logically ought to have been discovered as it would've been if it were a citizen's corpse, e.g. check if killed by player's citizens/traps (implies having seen the corpse). I don't know if it's possible to actually check if any citizen had seen the corpse (apart from recent thoughts, which isn't permanent).
That said, I've always thought the tool's existing ability to discern from a crundle skeleton no one's ever seen before in the cavern as the handiwork of a rampaging FB as somewhat armok-y. It somewhat fits the "info the game intentionally keeps hidden" category, but on the other hand it hardly counts as god-like powers. But I think the strongest argument for it to not count as armok level is the fact that decorations, statues, and wall/floor engravings already do reveal the cause of death even if the slabs only say they went missing.
I just found out that setting incident.flags.discovered to true for certain creatures will make the game automatically assign a tomb for them if available. As far as I can tell it seems to affect sentients only, or at least those that leave a corpse that has the dead_dwarf flag. This is probably not a desirable behavior, though I'm not sure if there's a way to work around or mitigate it.