It's a pretty standard World War 2 era lantern, with some metal shutters welded on to protect the glass inside and to keep light from leaking out. Soldat opens them to show her the golden glow inside, and the one little crack leaking green light instead. The steady light is clearly not fire, though it works like fire if you try to light things on it, and if her scanner picks up such things, it's definitely life force, a soul, whatever one might call the thing that makes someone a living, unique individual.

"Depends on who it is," they say. "Devero knows about this already, and he's pretty handy, he helped me tune up the arm once. Raven knows too, she's more magic-inclined. Who were you thinking."