alien isolation anesidora alien silhouettes

Even if you were to wave the white flag and scream your lungs out about your harmlessness, they almost certainly wouldn't believe you.

By this point, it's safe to assume that the inhabitants of the Sevastapol have degenerated into groups of looters and survivalists, fending for themselves and skirmishing with other bands of people over what were once simple amenities like food and water.

This is a survival horror game, so you should be able to avoid violent confrontations unless they're absolutely necessary, right? Why can't Ripley just yell 'Stop! I'm not your enemy!' or something like that when she's confronted by them? The survivors are paranoid and on-edge, sure, but they're (hopefully) not psychopaths.

The overly trigger-happy human survivors on the station, and their unchallenged habit of performing Poor Communication Kills.

Standard light armor-piercing rounds.' That's the reason why the Pulse Rifles are able to shred through the xenomorphs and Gorman's gun in the above mentioned scene would have likely use regular 9mm ammo, which would explain why the rounds just bounced off of the one he was shooting at.

This is true, as the M-41A pulse rifle's ammo is described as 'ten millimeter explosive-tip caseless.

Gorman fires off a few headshots with a pistol which do nothing but skim off with a few sparks it's likely the Xenomorphs have a level of resistance to gunfire, depending on the caliber and type of ammunition. In the vents, Gorman goes back to rescue Vasquez and a Xenomorph climbs out of a grate.

This is reinforced by a quick scene in Aliens.

The guns used in Aliens fired an explosive bullet which is why it so deadly. Its likely the the alien can survive a mere bullet wound as they are touted as the Ultimate Lifeform.

The alien will actually bleed if you shoot it but it won't kill it (and fortunately its blood won't kill you).

Plus, in most scenarios where you are firing your weapons at the Alien, you are not likely going to be alive long enough to see it die from its wounds.

You likely kill several Aliens during the game, they just survive long enough to escape and die out of sight and get replaced by another one without your knowledge.

The Alien isn't immune to your weapons, your guns just aren't of sufficient quality to kill it instantly (compare with the weapons used in the sequel which were top of the line military grade weaponry.).

The answer to this is actually fairly clever.

Alien isolation anesidora alien silhouettes