Not every Pokémon-themed handheld has to be covered with Pikachu. This lucky fan-made Game Boy Colour for example has the entire region of Kanto painted on its front by Belgian graphic artist Vadu Amka.
The purpose of this creation was to give the illusion that it's an old and mysterious artefact found in the ruins.
Here are some zoomed-in shots. Cool details of Kanto indeed: