Art therapy: Grumpy Cat coloring page is an online game and printable coloring book that never ends. Choose a coloring mode, from standard coloring using a wide range of tools, to a game by numbers that children will enjoy and improve attention. Invite children to draw – this allows you to unlock the potential of a young artist and develop his unique abilities! Creative Commons Attribution-NonCommercial 4.0 License. Author of the work: Persimmons Studio.