Sega Master System / Mark III / Game Gear
Take control of a kung-fu expert and battle it out across a horizontally scrolling landscape beating seven kinds of shinola out of anyone stupid enough to cross your path.
Similar in many respects to the old coin-op, Kung-Fu Master, but with more variety and better graphics. Black Belt is a tough and challenging beat em up with an army of baddies to kick m, and hard end-of-level baddies to overcome.
It's definitely one of the better Sega beat em ups around, and is highly recommended.