Playing adventure mode, I saw an alien that I thought at first was a building (sort of looks like the tower in Seattle), but then it started floating up in the air and attacked me. I ended up killing it and got lots of tech parts including microprocessor chips. I've never seen it again, and I didn't think to take a screenshot.
It looked like a round alien ship with lights on it, with a large long pillar underneath it, and 4 long tentacles that droop down. When it flies, the tentacles spread out.
What is this thing? And does anyone have a screenshot or link to a page about it? I've been googling for half an hour and can't find any info or a picture of it.