who just locked down the facility and wrote it off as a lost cause.
Most of them will attempt to shoot at the player. On lower-risk planets (i.e., peaceful ones like Garden or Forest biomes) these are generally limited to the odd ruins of a stone or wooden house, but on more dangerous planets such as those with a Toxic or Scorched biome the background picture makes it pretty clear this planet used to have a pretty advanced civilization until the climate went to hell.
There's also the tiny matter of the fact that it is completely invincible. It will constantly advance on you, and has a corrosive aura that kills you in seconds if you get too close. The Erichus Ghost begins to hound you the second you mine a single bit of fuel from a moon.