Tactics and Dogma
Deciding that clobbering every single one of them was not worth your time. You moved on, moving without a trace, as silent as a marine in combat armor could be, which is very quiet compared to these aliens whooping and hollering like amatuers.
as you roofed pass the ammo bay a single box gets your attention and you open it with a loud clack.
Inside is bits and pieces, obviously for a railgun. such valuable equipment would make a ship mounted three-meter molybdenum Steel Bearing accelerator a semi-auto weapon. Such glorious equipment is perhaps one of the most valuable things a Railgun Operator could ask for, as it turns their job from manually setting each and every pellet to loading the internal magazine with clips and calling it a day. You dool a little with marine pride.
You leave the room, the orc'n'bot smash over, both are alive, missing limbs. You move away, far far away from the hell hole camp.
You tinker with the equipment, attaching it to the Mark 1.1 Railgun with adapt hands, experience guiding your aged hands, you idly note through one of the mirror-polished surfaces of your weapon that you have large eyes and a cute button nose.
the Xeno was sleeping in a cubby hole while you tinkered for the six hours it took, and you heard a gruff voice just as you finished, speak.
It was a harsh and gurgly voice, exactly like an Orc.
"Yersh duh diemone?"
Your blood boils a to a low simmering rage, and you turn around with the railgun in hand, the autoloader already primed a shot to fire, and the Orc in front of you was the same one that brooded in the corner, his pack filled to the brim with enough explosives to most likely cause a hole in the ship and kill at least a tenth of everyone onboard, Not you of course. your too much for weak sauce explosives to kill.
What do?