God Mode
     Locate  the  difficulty  files in your Crysis installation folder
(ie:   C:\Program   Files\Electronic  Arts\Crytek\Crysis\Game\Config).
These  files  are called diff_easy.cfg, diff_normal.cfg, diff_hard.cfg
and  diff_bauer.cfg.  Open the file (with Notepad) that corresponds to
the  difficulty  level  you are playing. Add the following line to the
end of the file and save it:

g_godMode = 1 

     Now,  when  playing  your health will still decrease but you will
not  die.  Instead, your health and armor will automatically replenish
when your health reaches 0.

Unlimited Ammo
     Using the same method as above, add the following line to the end
of your config file:

i_unlimitedammo = 1   (Unlimited Ammo)
ai_IgnorePlayer = 1   (Enemies Ignore You)
i_noweaponlimit = 1   (Carry Unlimited Number of Weapons)

Your ammo will be frozen in the game. 

NOTE: ALWAYS MAKE A BACKUP BEFORE OVERWRITING GAME FILES.


You can also modify your suit stats. For example:

-- Player Health/Energy/Suit
// No energy loss
g_suitCloakEnergyDrainAdjuster = 0

// No energy cost
g_suitRecoilEnergyCost = 0

// Run faster
g_suitSpeedMult = 2.85

// More armor points
g_suitArmorHealthValue = 900.0

// Instant health regen
g_playerSuitArmorModeHealthRegenTime = 0

// Instant health regen while moving
g_playerSuitArmorModeHealthRegenTimeMoving = 0

// Set health regen time to 0
g_playerSuitHealthRegenTime = 0

// Set regen time while walking to 0
g_playerSuitHealthRegenTimeMoving = 0

// No waiting until regen starts
g_playerSuitHealthRegenDelay = 0

// Instant energy
g_playerSuitEnergyRechargeTimeArmor = 0

//Instant energy while moving
g_playerSuitEnergyRechargeTimeArmorMoving = 0

// Set energy regen time to 0
g_playerSuitEnergyRechargeTime = 0

// Do not wait until energy regen starts
g_playerSuitEnergyRechargeDelay = 0

// Extra health
g_playerHealthValue = 900.0

// Set difficulty, 1 is easy, 4 is most difficult
g_difficultyLevel = 1

     After making all of your edits, save the file, load up a new game
and see what you've edited!


Developer Mode Cheats
     Start  the  game with the command-line shortcut of -DEVMODE. This
will enable new cheat keys that can be used in the game.

Example: "C:\Program Files\Crysis\bin32\Crysis.exe" -DEVMODE 

Cheat code:              Effect:
F1                       Toggle First/Third Person View
F2                       Jump to Next Checkpoint
F3                       Toggle Fly Mode/Ghost Mode
F10                      Jump to Previous Checkpoint
NUMPAD 1                 Give Missile Launcher, Shotgun, Alien MOAC
NUMPAD 2                 Unlimited Ammo
NUMPAD ENTER             DEBUG MENU

     In  addition to these cheats keys, you can now use the console by
pressing ` (tilde) and typing any of the following commands:

Cheat code:              Effect:
r_displayinfo 0          Remove Debug/Devmode Info from Screen
g_godmode 1              God Mode
i_noweaponlimit 1        Carry Unlimited Weapons
i_unlimitedammo 1        Unlimited Ammo
i_giveallitems           Give All Weapons
i_unlimitedammo 1        Unlimited Ammo
i_giveallitems           Give All Weapons

:


g_suitSpeedMult = 2      Faster Speed

ai_UseAlternativeReadabilityKoreans 
                         Speak Korean
                         
V_goliathmode 1          Indestructible Vehicles 
                         (Affects Enemies Too)

Unlimited Nightvision
Enter the following commands into the cheat console:

hud_nightVisionConsumption = 0
hud_nightVisionRecharge = 999