What we know about Engineers so far

Infos gathered from the commentary, many interviews.

-LV-223 was a military outpost. Confirmed by Ridley Scott on the commentary of AC.

-Engineers are not gods, just superior beings. Confirmed by RS on the commentary of AC and many interviews.

-Engineers (in the context of those from Planet 4) have a lifespan of around 150 years. Explained on the commentary of AC by RS.

-The giant stone heads inside the citadel represent 6-7 elders of the entire civilization; Intellects, artists, wise men. Confirmed by RS on the commentary of AC.

-The artbook also described the giant stone heads as a way Engineers celebrate themselves. Like a depiction of false gods watching over everything.

-Beings on Planet 4 are Engineers. This was confirmed by the filmmakers in the interviews, commentary of the film, artbook, and the people who played them.

-There are female Engineers. Females are seen in the flashback and in some of David's illustrations. Also, people who got to play these Engineers said
there were females on the set.

"Now this is a good question! We worked with a second unit that day and the second unit director wasn’t giving much away to what we really were but they did confirm we
are Engineers! And the costume designer called us all “her Engineers” so we do know we are 100% Engineers but I do believe our origins is something
M.r Scott is holding close to his chest… what I will say there was speculation that the Prometheus Engineers where more like a military type rather than our more
civilian look I think all will be revealed if Sir Ridley gets his way and films the next one."- Billy Mansell on AVP Galaxy interview.

-The Engineer's role is evolution. Explained on the commentary of AC by RS.

-Ridley Scott also said that he sees Engineers as gardeners of space.

-During a podcast with empire magazine, Scott explained that the Engineers visit planets they seeded with life to check on them, and to update them. If their creations proved
to be a disappointment, the Engineers would wipe out the whole planet and start all over again.

"If the planet went wrong, they would want to wipe it clean. But that could take 500 years. When they revisit –
because different visitors would come back and see we’re not doing so well – they would look at these human beings that are jerks,
that are killing the planet, killing themselves, can’t settle down, they’re like a bunch of children. We should wipe it clean."

-Ridley also mentioned on the commentary of AC that the Engineers let their children, human beings, get out of control. So humans are both no longer valid
or useful.

-Despite being more powerful than humans, Engineers were defeated by their own invention. Explained on the commentary of AC by RS.

-Engineers send their ships on different intervals. When Shaw and David's juggernaut arrived, there was a welcoming ceremony occuring as 2 million Engineers
gathered at the plaza, welcoming the juggernaut's arrival. When David unleashed the ampules, they were shocked by the act. Explained by RS in the commentary of AC.

-Scott James, the guy who played the Engineer in AC, in AVP Galaxy interview also indicated that Engineers send their ships on various missions.

"The Engineers send the crescent-ships out on a various mission and they return infrequently. It’s a very big event and those at home make the effort to show their respect and welcome the ships and their honored crew home. This seems consistent with the ritualistic and important ceremony afforded to the sacrificial Engineer in Prometheus. No-one was expecting David’s ship back, but they’re obviously a trusting race…a bit too trusting maybe! They realize something’s wrong when the cylinders drop but don’t know what’s happening then yeah…it becomes pretty apparent after it’s too late."

-Ridley Scott and Damon Lindelof mentioned this many times before, but they speculated that The Engineers didn't originally create the black goo.