To open the cheat menu, which has all the classic Duke Nukem cheats available in it, do the following at any point during the game: Press Down, X, R3, Right. Make sure to use the D-pad for the directionals and not the stick.
Easier final Boss
If you have a jet pack, fly up and destroy the beer blimp. Guns and health will scatter on the ground, allowing the final Boss to be killed easier. Note: One of the best weapons to use against it is the Devastater.
Easy "Alien Maggots Are Gonna Pay" achievement
Play Episode 1: Mission 1 - "Hollywood Holocaust" on the easiest difficulty. From the start of the mission, fall down the ventilation shaft, and run directly to the alley behind the movie theater. Use the pig cops as platforms to jump onto the small lip running along the wall. From there, go to the bridge. Once on the bridge, run past the pig cop and end the level to get the "Alien Maggots Are Gonna Pay" achievement.
Easy "Oomph, Uugh, Where Is It?" achievement
This achievement can be earned through normal progression, but you can grind by repeating the same mission multiple times. The achievement counts secrets found across all playthroughs rather than the number of unique secrets discovered.
Easy "Shake It Baby" achievement
The first time that this can be done is during Episode 1: Mission 2 - "Red Light District". Enter the strip club, walk up to a stripper, and press [Interact] to get the "Shake It Baby" achievement.
Secret level in Shrapnel City
Go to the Hotel Hell level, then go to the fountain by the pool. Step through the waterfall, then go behind a bush. You will see a radioactive waste sign like the ones that mark the end of a level, except it is gray. It will take you to the secret Freeway level.
Tier Drops level in Shrapnel City
There is a tenth level in Shrapnel City called Tier Drops. To get there, go to the movie level, and go to the stage with the NASA sign and the body parts with a telescope. Kill the alien with the chain gun, and press [Use] on the sign. A door should appear with the caution sign that ends the level. Do not go to the stage with the ship or this will not work.
Various Achievements
Complete the following achievements to unlock Microsoft Gamerscore points.
Achievement
How to unlock
Points
Alien Maggots are Gonna Pay
Finish the "Hollywood Holocaust" level in under 3 minutes.
40
All Too Easy
Find a secret area.
15
Buzz Off
Kill a Firefly Trooper while it's flying small.
15
Cheating!
Use a cheat code.
15
Come Get Some
Complete "Shrapnel City" on any difficulty.
80
Damn, I'm Good
Complete "The Birth" on any difficulty.
80
Doomed Marine (secret)
Find the Doomguy in the Level "Death Row"
15
Duke's Mighty Foot
Step on 40 enemies after using the Shrinker on them.
40
Duke, Use the Force! (secret)
Find Luke in the Level "Lunar Reactor"
15
I Never Inhaled
Use the hookah in High Times.
15
I Never Knew This Was Here
Finish a secret level.
15
I'm Back, Baby
Complete "Alien World Order" on any difficulty.
80
Invaders Must Die!
Kill 1000 enemies.
40
It Happens
Step in a pile of excrement.
15
Let's Rock
Complete "Lunar Apocalypse" on any difficulty.
80
More Than 2 Weapons At Once?
Carry all weapons with ammo at once.
40
Nukem All
Kill 5 bad guys with one shot.
40
Oomph, Uugh, Where Is It?
Find 70 secret areas.
40
Piece of Cake
Complete "L.A. Meltdown" on any difficulty.
80
Rage Engage
Kill 10 bad guys in 10 seconds while on steroids.
40
Roast 'Em
Burn 50 bad guys to death.
40
See, I'm Tough Too!
Finish any level on "Damn, I'm Good" difficulty.
60
Shake It, Baby
Tip an exotic dancer.
15
Smoke 'Em If You Got 'Em
Use the Incinerator
15
Take No Prisoners
Kill every enemy on a level.
40
That's What She Said
Listen to Developer Commentary (Use at least one trigger).
