Use processing to draw an animal where you will use a single part of the animal so that this part appears to follow the cursor around the screen. also you can add a tongue to the animal, which appears to follow the cursor. The tongue is a triangle, with two coordinates anchored to the frogs face, and one coordinate that moves around, not too far from the face, but always towards the direction of the cursor.

You could make eyeballs move in eye sockets, you could make a wing move or an animals tail move. You just have to make some part of the animal visibly pay attention to or seem to follow the mouse cursor as it moves around, even as the cursor is being used to adjust the scaling with the sliders.