Ranged Attacks on Vacuum

Depends on the medieval physics one believes in. In a system including ether as the ur-medium, if Vacuum also includes a lack of ether, motion shouldn't be possible at all! (Of course, neither should vacuum or negative energy, but that is another story).

As a matter of fact, travelers to Vacuum experience a tiny amount of pressure and temperature -- enough that the dangers they face there are cold and suffocation, but not decompression and freezing solid. I suspect that they're being affected by, not nothingness, but the elemental essence of nothingness, which is itself something -- enough for egarus to feed on, give a traveler taking the long drop a (very high) terminal velocity, and eventually drag an unattended item (one that isn't imagining any gravity) to a stop.