Unlock Cheats
     Beat the game once With 100%

Unlock Ragnarok Assault Mech for Multiplayer
     In the mission "Divergent Entry," you must climb a wall to access
the  second  area. To your right, you will see a closed bunker. On the
left  side  of  this  bunker  is  an access terminal. Beat the hacking
minigame  to  open  the  bunker.  Inside,  you  will find the Ragnarok
Assault Mech. Beat the level in this mech to unlock it for multiplayer
use.