Because the game is no longer sold on primary markets, digital preservationists have archived various versions:
: If you are revisiting the game and need a boost, classic Duke Nukem cheat codes (like G+O+D for invincibility) are often documented by community wikis. DN: Manhattan Project (mods, addons and etc.) - Page 5 Duke Nukem: Manhattan Project Free Download (In...
If you are looking for a way to play the game today, you have several reliable options: Free Legal Downloads & Archive Versions Because the game is no longer sold on
The classic side-scroller , originally released in 2002, is currently considered "abandonware" by many communities because it was delisted from major digital storefronts like Steam and GOG.com due to licensing changes. Paid Digital Availability
: If you just want a taste of the gameplay, the original demo is also hosted on the Internet Archive. Paid Digital Availability