Some really creative ideas in this thread :) There's so many ideas here but I only have time to comment on a few.
@Collol: Here's a suggestion for the color of the eyes- what if you made them yellow? It could be interesting with a blank eye look and ties it back to the corn idea. (something like a dried out straw-like yellow to go with the husk concept I guess). I actually didn't notice the pupils at first but when I did, I think I liked the idea that it didn't have pupils to go with the above suggestion.
@Kadew: I love your idea, something that looks as innocent as a sloth and then boom! murderous grass sloth! I can see it suddenly dropping down from trees if you're not careful in the forest or something lol.
@Magistrum: One of the strongest designs and partly why I couldn't come up with any good wood-based designs heh. I love how you integrated the lines you see in tree trunks and hollows. Someone said about adding green, maybe just make its body (not the wood-covered parts) have a subtle shade of dark green so it's less gray? Maybe that could be enough, otherwise I love the autumny color scheme.
@Yilx: (cactus flower) I think probably one of the best proportioned designs. I love the horns on its head and it looks quite menacing and cute at the same time, and I think the horns and the arms make it stand out from Cacturne. The colour-scheme in the future will probably make it stand out even more but I do love how you arranged the thorns in its body with the leading lines.
(Vampire heart) very interesting concept and maybe it's the added colours but its a very strong concept for the typing. I love the expression on the mask/flower thing although I feel the body seems a bit too stick thin, even if it is a vine/stem. It seems quite empty in contrast to the very rich design of its top half.
@Quanyails: I think the top left one is the best in terms of the bottom half. The bottom left seems less of a Grass type now that it seems more human-like with arms. Maybe if you go with the top left and it has extendable vine-like arms with its scythes?
@Choms: This is a really interesting concept. I love the colour scheme, it has the perfect mix of colours for both types and isn't so dark that it obviously screams Dark type- which is good. The red eyes really help.
@Koa: I really love the concept of the shade but I feel maybe the leaf should be attached to or integrated more to its body or something. Maybe the back of its head, shoulders or back?