|
A Belker can turn to smoke, enter an occupied square, and try to force the occupant of the square, to inhale a part of itself. If the Belker is attacked, does the square's co-occupant run the risk of injury from the attack? The bestiary doesn't say, but it sure seems likely to me that it would.
Co-occupants of squares only take collateral damage from attacks aimed at other co-occupants if there's a special rule attached to the them, such as cloakers or such. I don't see any such rule for a Belker, although it does reference gaseous form. Nothing in the gaseous form spell talks about damage to creatures in the same square.