Shockingly-good for a late era NES game. The Manhattan Project is basically the younger brother of the SNES's Turtles in Time, and it's a very fun and well-polished beat-em-up with great graphics by NES standards and a nicely-implemented co-op mode. Definitely worth a shot if you're a Turtles fan or looking for something new to play on your Everdrive or emulator... because uh, yeah this one's really expensive unfortunately.