alien

I'm working on a sci-fi story about an alien race invading earth. I've got two types of invaders picked out already (slimes and illithids/mind flayers) and I want to add a third. The best I can think of are futa-amazons but that might be too boring compared to the others. Thoughts? Suggestions?

what alien, mythical, or nonhuman features do you think would be cool or strange to have or have in a lover? doesn't need to be inherently sexual. anything from multiple limbs to tendril hair to a studded ovipositor with a knot. i honestly am just used to making humanoid amazon creatures and...