Concept Art: Weird Swamp Critters

Back to Uni again now that the second semester has begun, I've got some fresh new concept art. The project, much larger than our previous ones, is to design a main character and two sets of enemies, then sculpt high-resolution 3D Models of one main character and one enemy using ZBrush. So far, I've drawn up one set of enemies. My basic ideas were 'lots of teeth' and 'plant creatures'. As you can see, a few of the designs mix both ideas, while the rest lean to one of the ideas. My favourites are the top-middle and bottom-left creatures. I'm especially happy with how the bottom-left chicken-legged monster turned out, from such a simple base (a circle with a crescent attached). And I love the top-middle creature, simply for it's oddity. How does it find prey, when it has no eyes or ears, just a big-lipped mouth? How are the vines growing off it's back? Is that a beard of grass and roots? I really do enjoy my work at times.