aaa i love that you have a range of fauna omg this is super cool?? your concept art is so interesting to look at i love it! if you're interested in toon shaders i'm pretty sure there's an example ue project that has some examples--they're a bit complex so maybe you can stick with unlit materials for the moment. unreal is a lot but once you break into one 3D game engine the others start to make a lot of sense faster! best of luck!!