>>528631561
>Is Skinflint immortal in vanilla SoC?
No, he isn't.
>I can't figure out how to reverse it.
You might have to edit all.spawn. Unless they made ALL traders invulnerable via configs, in that case it may be easier.
Try going to gamedata/config/creatures/m_stalker.ltx and check the [stalker_trader] section. If it has its own immunities section, where every value is set to zero, delete it; if it doesn't and just inherits them from the "stalker" section, then they might have assigned Skinflint a different section in all.spawn or made him immortal by some other means.
Might also check his logic in config/misc/gulag_mil_freedom1.ltx, in case they've done it through scripts or something.