The leech is the alien's mining structure. Like a mushroom extracts nutrients from the ground, this similiarly shaped creature sucks some invisible resource right out of the air (it competes with the human mining structure). It can be built on walls and ceiling in addition to the floor and thus needs to roughly fit into a cube for technical reasons. Concept by Khaoz.
Animations should include idling, pain and death and they should look fitting regardless of the orientation in which the structure is built. You can animate yourself or have us assign this to a specialist.
Since this is your first alien buildable model, you might want to have a look at other threads where I gave some additional information about the style we are heading for, such as that of the Booster.
Note that the leech is, in terms of alien evolution, a very old and basic structure as it extracts the resource that is used to grow all the other alien buildables. Therefor it does not need to have a face, which is our usual recurring element.
The closest relative to the leech is probably the egg, the structure that aliens spawn from:
The creep stand should be much more subtle and filigree, similiar to the egg I posted. Note that we are currently blending another texture below the feet of our structures (as the one you can see on the picture where the egg hangs from the ceiling, even though that one seems to have a graphics glitch according to its low brigthness) and we might even start to use procedural geometry for this at some point in the future. Therefor structures don't need to (and shouldn't) provide much of this "creep" on their own, in fact the egg and the leech are the only structures that show some of it as part of the model. However, the less they show, the more freedom we have when we generate it live.
The head should be wider. Imagine a cube that has one face on the floor and the tip of the leech's head in the center of the opposed face. The head should fill out as much as possible of this cube (without looking square itself, obviously). This is important gameplay wise because we use the bounding box of models for collision detection (and currently also for hit detection) and since the leech can be built on surfaces of any angle, its bounding box should describe a cube. (More precisely, the bounding box is later set manually, so it's fine if small details stick out of it or a part remains unused.)
The shape of the head, apart from being rather thin as explained above, looks a bit like a helmet currently. The motive behind the concept's shape is a mushroom (just like fungi, the leech sucks resources out of its environment), so the head shouldn't be symmetrical. The two bubbles on the concept are just an example of cysts that could cover its surface, I guess they should actually be a bit smaller and more frequent.
The part that connects head and stand should be a tad thicker and more dense.
If you are unsure about anything or need further inspiration, think of mushrooms.
Much better, but you should move the head further down and make it less oval and more (rotationally) symmetric. The bounding box that shows on your screenshot should ideally describe a cube.
