Morph:
Press the 'Enter' key during gameplay then type 'mpmorph' then whatever you want to morph into, for example: 'mpmorph queen'. Then press 'Enter' to activate the cheat.
Press the 'Enter' key during gameplay then type in the following codes followed by 'Enter' to activate the cheat.
Turn rotation display on/off:
mpgrs

Turn size display on/off:
mpsizeme

Turn invinicibility on/off:
mpcanthurtme

Unlock all weapons and ammo:
mpshuckit

Turn speed display on/off:
mptachometer

Restart level with defaults:
mpbeamme
No clipping on/off:
mpsixthsense

Get full armor:
mpsmithy
Get full ammo:
mpkohler
Full ammo:
mpstockpile
Unlimited ammunition:
mpbunker

No clip on/off:
mpsixthsense
Third person view on/off:
mpicu
Show position:
mpgps
Edit FOV value:
mpfov

Edit light amplification:
mplightadd
Edit light scale:
mplightscale
Edit vertext tint:
mpvertextint

Edit weapon breach:
mpbreach

Edit weapon offset:
1mpwmpos

Edit weapon offset 2:
mpwpos

Level select for all three species:
mpxfiles
Set health to indicated number:
mpdoctordoctor

Warps character speech:
mpmillertime