The levels of Duke Nukem: Manhattan Project take the player through the skyscrapers and buildings of New York City, nightclubs, warehouses, streets in Chinatown, gritty subway stations, a G.L.O.P.P.-infested sewer, factory, a tanker, G.L.O.P.P. rig and finally, a space station. The levels are quite linear compared to other Duke titles, but they still have secret areas to explore. The game uses the Prism3D engine, which allows for full 3D view in some parts rather than the standard side-scrolling platformer fare, giving it more depth. The game has eight chapters, each of which are divided into three parts (levels).
The level designers are credited as:
- Lead level design:
- Robert Travis
- Level designers:
- Jeremy Blumel
- Matt Harris
- Kris Stout
- Chris Voss
- Additional level design:
- Jan Kondpasek
- Sean Lynn
Chapter 1 - Rooftop Rebellion Edit
This chapter takes place on various skyscrapers and buildings of New York City. After Duke makes his way to a building rooftop, he encounters Mech Morphix in a helicopter piloted by a Pig Cop who fires a rocket at him, blowing Duke away. Duke gets up and destroys the helicopter's rocket launcher, then kills the dispatched pig cops sent to kill him, before finally grabbing the chopper's ladder and blowing off its jet engine, sending it down to crash, however both Duke and Morphix survive.
Chapter 2 - Chinatown Chiller Edit
This chapter takes place in Chinatown, New York City, where you go through various streets, a warehouse, a nightclub (Club Ming) and more. Your objective is to get to Club Ming where Morphix is hiding, but after getting there, Morphix is revealed to have left, instead Duke encounters the club owner. After beating him in combat, he goes kamikaze (bombing himself), but Duke remains completely unscathed due to the weak force of the blast. He then jumps into a hole, into the subway.
Chapter 3 - Metro Mayhem Edit
Set in a subway. You'll encounter the boss on a train.
Chapter 4 - Unholy Underworld Edit
Set in a sewer and discarded subway station, much like an underworld indeed. You'll encounter the boss amidst cockroach eggs. After she is seemingly crushed by a monolith from the ceiling, Duke will take the train and escape, only to be followed by the queen, who eventually will end up getting run over by a train car, right after Duke jumps off from it.
Chapter 5 - Fearsome Factory Edit
Set in Morphix's G.L.O.P.P. facility. The boss is the Ratoid with the battle taking place on an elevator.
Chapter 6 - Tanker Trouble Edit
This time you'll be in Morphix's mutant-infested, G.L.O.P.P.-storing tanker. The boss is the Mutated Fly who has the ability to become invisible for very limited periods of time.
Chapter 7 - Deviant Drilling Edit
Takes place in Morphix's G.L.O.P.P. rig (compare to an oil platform). The boss is the Fem-Mech. After annihilating her, Duke heads to the teleporter, where he'll be transported to the space station.
Chapter 8 - Orbital Oblivion Edit
This final chapter takes place in Morphix's space station. After making his way to the final room, Duke encounters him for one last battle against a huge cyborg Morphix modeled specifically after Duke's likeness. After destroying the cyborg, Duke heads to the space pods and arrives safely back in New York City, while the space station is devastated in a giant explosion.