Machine Gun Kick-Found on "The Chase: I need an Exit Stage" to unlock, Find the breifcase in the corner of the market area behind the fruit stands
Quick Kicks-Found on "Storming the Drain" Stage, to unlock, in the 2nd to last room, use the ledges along the wall to reach both of the top two platforms.
The Beginning of the End-Found on "Seraph's Apology" Stage, to unlock, once you return to the teahouse from the theatre, destroy all 8 colums and a table to get a breifcase
The Code Breaker-Found on Weapon's Training Stage, to unlock, Find the breifcase among the Operators secret stash in a dark upstairs room
The One-Found on "The Burly Brawl" Stage, to unlock, Defeat 30 Smith's before the level ends to make a breifcase appear in the center of the level, claim it.(crazy hard to execute)
Ultimate Hyper Strike-Found on "Redpill Rescue: Security Gaurd" Stage, to unlock, Defeat the 5 members of SWAT by the stairs in 30 seconds, frag grenade easiest way.
First Complete the game in hard mode.
Then go into 'cheats' and go to the code that says 'Lots of guns'.
You will get some of the best guns at the start of every mission.
Have fun shooting Agent Smith and much much more.
In the security guard level, there is a glitch for the bonus objective where you have to defeat the SWAT team in 30 seconds. you can avoid doing this by running up the stairs and ignoring them. you should be able to complete the bonus objective like this.
1. Attain and select The One difficulty on the first level.
2. Use level select and go straight to the last level and then defeat the Giant Smith.
Once you've done that the game will believe you went through the whole game on Hard mode and you will have unlocked all the cheats.
* Level Select is needed for this to work so you would have obviously had to have completed the game before, be it on Easy or Normal difficulty.
If you run down the subway tunnel in the Subway Showdown level, the train will automaticly come. Use this to knock Smith down the tunnel, and run back out.
There are 6 cheats in total and you unlock 2 for each difficulty completed.
Completing Easy unlocks;
"Lots of Guns"
At the beginning of virtually every level, Neo starts the action automatically armed with some of the best weapons in the game.
"Indestructible Melee Weapons"
Most Melee weapons shatter after a few swings. With this setting active, all of Neo's melee weapons are indestructible.
Completing Normal unlocks;
When enabled, Neo gains health by wounding or killing enemies.
Activate this setting, and Neo's firearms will never run out of ammo.
Completing Hard unlocks;
Bullets bounce harmlessly away from Neo when this setting is active.
Neo is already The One. But with this setting, he really is in God Mode!
Completing the game on The One (Hard) difficulty setting will unlock all the cheats.
On the first level your skill is tested against waves of enemies, you then get to choose your difficulty depending on how many opponents you defeated.
Defeat Smith at the end to unlock the hard difficulty setting.
On the Upgrade Screen, activate the Atman Principle "Spoon" to unlock the Zion Archives.
You can find the Zion Archives at the very end of the Level Select screen.
"The One" Difficulty Mode - Successfully complete the first level without dying.
God Mode - Complete "The One" Difficulty Mode
Infinite Health (God Mode) - Beat the game on Hard
Unbreakable weapons & All weapons - Beat the game on Easy
Vampiric Health & bullet reflection - Beat the game on Normal