As a whole, I think your work throughout this lesson is really well done. There are a couple points I'm going to call out to help keep you chugging on the right path, but in general your constructions are very solid and demonstrate a strong grasp of how these forms exist together in 3D space.

Starting with your organic intersections, you've established how the forms slump and sag over one another in a consistent, believable manner, and I'm pleased to see that there are no contradictions in the directions in which the shadows themselves are cast. They all appear to adhere to a single, consistent light source.

Moving onto your animal constructions, you're definitely holding really well to the idea that construction is all about taking complex objects and breaking them down into simple forms, whose relationships can be defined and established in clear ways. There are of a few ways in which these relationships are established - or really, two main ones. There are the relationships between intersecting forms - like where you've done a great job of employing the sausage technique, and defined the joints between those sausages with contour lines. Then there are the relationships where one form wraps around the other - similar to the organic intersections.

In this second type, you've got some definite cases where you've handled them well, and some others which were still moving in the right direction, but had one key issue. If you take a look at this cat and this hybrid, they run into the same issue. The additional masses you've wrapped around their backs feature a corner that suddenly changes their trajectory, but with no clear reason for doing so.

We can also see this in some cases along some of your animals' legs, like here on the running wolf's foreleg. Notice how the form is wrapping around, then suddenly it shifts in its trajectory to run along the sausage's length? It creates a sort of "sausage in a hotdog" impression.

The key thing about having one form wrap around another is that every aspect of the new form's silhouette conveys something about that relationship between the two forms. We can think of each mass as it exists first in isolation, in its simplest form - just a ball of meat, made entirely of outward curves. As we press it up against an existing structure however, it takes on more inward curves in direct response to that contact. Every inward curve and corner has a cause. You can see what I mean here.

So the question becomes, how do we transition from the inward curve that shows how we wrap around the structure, to the more natural outward curve as we run along the structure's length? Well, you've actually done this somewhat correctly in some places - but to illustrate it more clearly, here are your two options. Either you create a more gradual transition that shifts smoothly from an inward to an outward curve as shown on the saiga antelope's back, or you ensure that you define whatever form your mass is pressing against to create that corner. The second option is more prevalent on legs, where we don't just capture the forms that stick out along the leg's silhouette, but also internal ones to help make the entire network of forms make sense. This can also be seen in the ant demo I shared in my Lesson 4 critique.

One point I did want to call out in regards to your additional masses is that you're relying a fair bit on contour lines - but those contour lines aren't necessarily doing much heavy lifting. When drawing a contour line, or really any mark, be sure to ask yourself what exactly it is meant to contribute to the drawing, if it's really necessary, and how to best achieve that result. Contour lines themselves easily result in diminishing returns, where the first one is vastly more impactful than the second, and the third even less so. If you're in a habit of just slapping contour lines on your forms without thinking about them, you'll want to try to unlearn that habit. In general, these additional masses can feel solid enough as long as you focus on how their silhouette defines that relationship in space, and avoid any unnecessary or unexplained complexity to that silhouette.

The rest of your work is coming along quite well, and I'm especially pleased with how you're paying attention to the way in which your head constructions all fit together as a solid, 3D puzzle. So! Keep up the great work, and I'll go ahead and mark this lesson as complete.