Sketch: Tortoise

I had saved a pencil drawing of a tortoise from the internet. Unfortunately I can not find the link to the original.
I wanted to try a light pencil layer first and then a final layer, but since I did not play around with brushes too much, it did not turn out the way I wanted.
Looking back, I should have used lighter and broader pencil for the first layer, and then HB, followed by darker (2B ?) at the end.
But all 3 of my layers were HB, same thickness.
I did a pencil drawing after a long time, and enjoyed the process.
Device: Lenovo Idea Tab
Software: HiPaint
Now that I look at the drawing, it looks like one of the hind leg is missing. Let us assume it is exactly behind the other hind leg and thus not visible 🙈