Last 1 min - insane spoilers don't read unless you have seen

[NGR01]

I really like this ending.

I have not seen the film but from the many descriptions I've read there is nothing to suggest this is some sort of Proto-Xeno. We have no idea what it is all about. The whole idea is wide open, especially when you want to consider the murals on the walls and the original purpose of man kind.

It is born from an Engineer and it looks like the creature from the altar murals in the ceramonial head room wich features a bowl similar to the one the sacrifice engineer uses to kill himself with and seed Earth with life.

Looks like the promethean myth is not only applied to the humans but the Engineer themselves. They worship some sort of death giving creature, that rip their chest open. They tried to tame it in that base but they all got infected and died.
Sacrifice is at the center of their way of life it seems, just like the original Giger mural unused in ALIEN. Now is the xeno their creation or actually a higher being is open to discussion.

[Parker]

keep in mind that most chestbursters have yet to "grow" their back tubes.  It's not even known if we'll ever see that particular creature again since Shaw heads off into the sunset towards another planet.  That was probably some extra cheese thrown in for the fans.  Not that I wanted to see that much cheese...

[NGR01]

keep in mind that most chestbursters have yet to "grow" their back tubes.  It's not even known if we'll ever see that particular creature again since Shaw heads off into the sunset towards another planet.  That was probably some extra cheese thrown in for the fans.  Not that I wanted to see that much cheese...

I'm kinda happy that this xeno was not just gratuitous and that something was set with the mural about him.
That creature is important to the Engineer, they have an altar with a mural featuring it.
We are definitly going to see it again if there is a sequel.
Lets not forget that the movie originally ended up with the survivors fighting the same creatures but fully grown.
I have yet to confirm if they were born from the surviving Engineer or were those that were born 2000 years ago when the outbreak took place.

[Xenoscream]

How do you know about another ending? Is there a script floating around?

The squid when it lays on top of the engineer once it's got him looks deliberately like a huge version of the facehugger, same colour and look as the top of a normal one.

One things for sure, don't mess with the black goo!