I was once looking for a model of a predator with an open mouth. So that there was a high poly, and not something remotely similar to a predator. I didn't find anything and had to do it myself. A little work in the blender and the model is ready. The pdo model with a closed mouth was taken as a basis. Reworked the mouth itself, aligned the mesh and completely reworked the back of the head. Well, I deleted a bunch of unnecessary polygons.