This is after I watched the demo. I learned a lot from the course, but needs to practice for a while to get them on paper properly. Cougth myself start to overwork things around the eye so stopped and made mental note that I might revisit the image in a few days. Still, I am quite happy with a few small things like the hippo feels moving due to the heavier weight on the front legs. I intentionally used some lighter weights at the back of the beast and tapered some internal lines.

I redid the exercise from memory. For the penguin I haven't seen the reference for half a day (and it shows, lol), while for the others I looked at it right before starting. I realized I'm executing the "loose sketching" idea completely wrong. I basically try to draw my lines as hectically as possible without thinking about it at all. Otherwise I can't achieve that sketch look anymore since my line quality is too clean now, lol. It still doesn't look like a sketch though, just like I was really lazy and impatient.