Another one of the many attempted Game Boy competitors that floated out of Asia in the early 1990s, like the Watara Supervision and Gamate. Unlike those systems, the wonderfully-named Mega Duck has hardware that's almost identical to the Game Boy itself, with only a few small changes to prevent cross-compatibility.
Released under a variety of different brand names around the world, rebranded the Cougar Boy in South America, and even had a learning computer variant made using the hardware.