Dark Lord is an action or RPG likely released in Japan for the NES. The developer and publisher are unknown without more research.   The title suggests a focus on a dark fantasy setting with the player possibly taking on the role of a villain or anti-hero.  Gameplay would likely involve battles with monsters or enemies, using various weapons or magic.   The game's graphics were likely in line with typical NES RPGs or action games.

Dark Lord (Japan)

Dance Aerobics (USA)