It's a bit hard to read at first sight due to the amount of information you got there, especially the red thing at the base of the mid pyramid in relation to the head of that guy, but i know is hard to work at that size. other than that, just great.
I love the composition and the concept. I didn't notice the Aquatoid at first, but when I did, it made me giggle. I would have loved to see a slightly bigger version, so you could have added more details. I demand moar X-com!
I <3 TFTD. Probably my favourite strategy game.
Anyway, mostly good, but maybe a little over-dithered at the top...
Die, aquatoid scum!
Colours are very authentic.
Edge of near pyramid and foreground undergrowth could do with some light AA.
Lobstermen AGAIN? Gah, where's my thermic lance?
The first thing I thought of when I saw this was X-Com! Great tribute :D
Nice sierpinsky pyramid!