Unlock the Making of Mission 4
At the Password screen enter XTRASCENEF.
Bullet shield mode
Enter "NOHITSFORU" at the Enigma Machine. If you entered the code correctly, green lights will flash. Select the "Bonus" option underneath the Enigma Machine to enable/disable this cheat. All bullets that are fired at you will be ineffective and will not damage you.
Unlock Achilles Mode
At the Password screen enter TODADOME.
Mission 3
Enter "STURGEON" at the Enigma Machine to unlock the Needle In A Haystack mission. If you entered the code correctly, green lights will flash.
Unlock M.O.H.ton Torpedo
At the Password screen enter TONSOFUN.
Unlock Men with Hats
At the Password screen enter MERCER.
Unlock Pefectionist Mode
At the Password screen enter ONEPMPCHMP.
Unlock Invisible Enemies
At the Password screen enter GHOSTSHOTS.
Unlock Sniper Mode
At the Password screen enter LONGVIEW.
Unlock Silver Bullet Mode
At the Password screen enter KILLERSHOT.
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