This is a nice drawing, though recent studies show that Dunkleosteus would have had a tail shape more similar to that of pelagic sharks.
@amur leopard Well, for doing the drawings, I first look up good images on the internet, ranging from Wikipedia, Google, Bing, etc. , in which I drag and drop them into the Photoshop canvas, then renaming simply as image. The second step is creating the drawing itself, in which I create random sizes for each canvas, while also enlarging it to fit in a proper position inside the canvas. For the third step, I create a layer known as a "Brush Layer", in which I use it for the basis of the drawing. Once I put the brush layer, then work on the drawing begins, which can be easy or hard (ranging from a few hours to 4 days or more) because at some point I have to take some time off due to schoolwork or any other personal issue I have to deal with. For the final steps, I use the paint bucket tool for coloring the drawing, and even I sometimes use the brush tool for correcting any mistakes I may have made while using the paint bucket tool, and I eventually enlarge the image or leave as it was in the canvas. The last step is that I use the paint bucket on backgrounds and using the text tool, I type up the name of the animal.
@The Cassowary Oh right. My bad. I just thought that the source basis for this drawing was accurate to me at first.